bluuebunny/crossref_metadata_2025 huggingface dataset:
The Study of Money
Authors: Kirshner Jonathan
Published: June 2011

Monetary phenomena define the contours of the contemporary global economy. This is a recent development, and it will transform the study of international political economy (IPE). Two excellent new books,The Geography of Money, by Benjamin Cohen, andMad Money, by Susan Strange, will frame, support, and provide the point of departure for scholars addressing this vital question. Ultimately, however, and perhaps necessarily, these books raise more questions than they answer. But they do suggest in which direction the most promising avenues of investigation point—toward the study of the unique interconnections between the ideas, material interests, and institutions associated with the management of money. Those relationships are profoundly consequential for politics and demand the renewed attention of contemporary scholars of international relations and political economy.
The Kantian Peace: The Pacific Benefits of Democracy, Interdependence, and International Organizations, 1885–1992
Authors: Oneal John R. , Russett Bruce
Published: June 2011

The authors test Kantian and realist theories of interstate conflict using data extending over more than a century, treating those theories as complementary rather than competing. As the classical liberals believed, democracy, economic interdependence, and international organizations have strong and statistically significant effects on reducing the probability that states will be involved in militarized disputes. Moreover, the benefits are not limited to the cold war era. Some realist influences, notably distance and power predominance, also reduce the likelihood of interstate conflict. The character of the international system, too, affects the probability of dyadic disputes. The consequences of having a strong hegemonic power vary, but high levels of democracy and interdependence in the international system reduce the probability of conflict for all dyads, not just for those that are democratic or dependent on trade.
The High Politics of IMF Lending
Authors: Thacker Strom C.
Published: June 2011

Analysts have long suspected that politics affects the lending patterns of the International Monetary Fund (IMF), but none have adequately specified or systematically tested competing explanations. This paper develops a political explanation of IMF lending and tests it statistically on the developing countries between 1985 and 1994. It finds that political realignment toward the United States, the largest power in the IMF, increases a country's probability of receiving an IMF loan. A country's static political alignment position has no significant impact during this period, suggesting that these processes are best modeled dynamically. An analysis of two subsamples rejects the hypothesis that the IMF has become less politicized since the end of the cold war and suggests that the influence of politics has actually increased since 1990. The behavior of multilateral organizations is still driven by the political interests of their more powerful member states.
Democracy, Indigenous Movements, and Postliberal Challenge in Latin America
Authors: Yashar Deborah J.
Published: June 2011

Scholars of democratic consolidation have come to focus on the links between political institutions and enduring regime outcomes. This article takes issue with the conceptual and analytical underpinnings of this literature by highlighting how new political institutions, rather than securing democratic politics, have in fact had a more checkered effect. It delineates why the theoretical expectations of the democratic consolidation literature have not been realized and draws, by example, on the contemporary ethnic movements that are now challenging third-wave democracies. In particular, it highlights how contemporary indigenous movements, emerging in response to unevenly institutionalized reforms, pose a postliberal challenge to Latin America's I newly founded democracies. These movements have sparked political debates and constitutional reforms over community rights, territorial autonomy, and a multiethnic citizenry. As a whole, I they have laid bare the weakness of state institutions, the contested terms of democracy, and the I indeterminacy of ethnic accommodation in the region. As such, these movements highlight the need to qualify somewhat premature and narrow discussions of democratic consolidation in favor I of a broader research agenda on democratic politics.
Loyalty Dilemmas and Market Reform: Party-Union Alliances under Stress in Mexico, Spain, and Venezuela
Authors: Burgess Katrina
Published: June 2011

Market reform has dealt a serious blow to traditional alliances between governing parties and labor unions. This article examines the fate of these alliances by applying a revised version of Albert Hirschman's schema of exit, voice, and loyalty to party-union relations in Mexico, Spain, and Venezuela. After refining the concept of loyalty, the author argues that it is embedded in the principles and norms on which these alliances are based. Market reform places party-affiliated labor leaders in a "loyalty dilemma" in which they have no choice but to behave disloyally toward one set of claimants. Their propensity to respond with either voice or exit depends on their vulnerability to reprisals for disloyal behavior and the party's capacity to retain their loyalty even in the face of sacrifices imposed on workers and unions. Both variables are linked to the authority structures in which labor and party leaders find themselves. In the short to medium run the alliances most likely to survive are those in which labor leaders have significant autonomy from their bases and/or in which the party is able and willing to challenge its own executive. In the long run, however, even these alliances may be vulnerable to collapse because of popular frustrations with the inadequacy of interest representation and the multiple pressures on political organizations to adapt to a more fluid and uncertain environment.
Partition as a Solution to Ethnic War: An Empirical Critique of the Theoretical Literature
Authors: Sambanis Nicholas
Published: June 2011

Theorists of ethnic conflict have argued that the physical separation of warring ethnic groups may be the only possible solution to civil war. They argue that without territorial partition and, if necessary, forced population movements the war cannot end and genocide is likely. Other scholars have counterargued that partition only replaces internal war with international war, that it creates undemocratic successor states, and that it generates tremendous human suffering. This debate has so far been informed by very few important case studies. This article uses a new data set on civil wars to identify the main determinants of war-related partitions and estimate their impact on democratization, on the probability that war will recur, and on low-level ethnic violence. This is the first large-N quantitative analysis of this topic, testing the propositions of partition theory and weighing heavily on the side of its critics. Most assertions of partition theorists fail to pass rigorous empirical tests. The article also identifies some determinants of democratization after civil war, as well as the determinants of recurring ethnic violence. These empirical findings are used to formulate an alternative proposal for ending ethnic violence.
Degrees of Democracy: Some Comparative Lessons from India
Authors: Heller Patrick
Published: June 2011

This article draws on the case of India to address the question of democratization by exploring the dynamic interplay of the formal, effective, and substantive dimensions of democracy. Fifty-three years of almost uninterrupted democratic rule in India have done little to reduce the political, social, and economic marginalization of India's popular classes. Within India the state of Kerala stands out as an exception. Democratic institutions have effectively managed social conflict and have also helped secure substantive gains for subordinate classes. Kerala's departure from the national trajectory is located in historical patterns of social mobilization that coalesced around lower-class interests and produced forms of state-society engagement conducive to democratic deepening. Contrary to much of the transition literature, this case suggests that high levels of mobilization and redistributive demands have democracy-enhancing effects.
The Effects of U.S. Foreign Assistance on Democracy Building, 1990–2003
Authors: Finkel Steven E. , Pérez-Liñán Aníbal , Seligson Mitchell A.
Published: June 2011

Democracy promotion has been an explicit doctrine of U.S. foreign policy since the end of the cold war. Between 1990 and 2003 resources for democracy programs increased by over 500 percent. Has this policy worked? Prior research has been inconclusive, relying either on case studies or on quantitative efforts that have not distinguished overall foreign assistance from democracy promotion. The authors answer this question using a new data set that includes program information for 165 countries for the years 1990–2003. The analysis distinguishes between direct and indirect causal mechanisms and employs a variety of statistical models that allow the authors to control for the unique democratization trend in each country when assessing causal effects, as well as for the potential endogeneity of U.S. democracy assistance. The analysis shows that democracy assistance does indeed have a significant impact.
The Normalization of an Anomaly: The Workers' Party in Brazil
Authors: Hunter Wendy
Published: June 2011

Drawing on historical and rational choice institutionalism, this article seeks to explain the evolution of the Workers' Party as it moved from opposition to government between 1989 and 2002. The Partido dos Trabalhadores (PT), a once radical and programmatic party, came to look more like its catchall competitors over time. This shift resulted from the heightened emphasis placed on immediate vote maximization after Brazil's adoption of market reforms rendered the party's socialist project unviable. Vote maximization made the PT more susceptible to the institutional incentives for building electoral and political support in Brazil, incentives that induce parties to weaken their programmatic positions, forge opportunistic alliances, and resort to patronage and even corruption. To grow, the PT ended up applying such tactics, which it had long condemned. Yet its adaptation was incomplete and uneven due to historical legacies that hindered change. The analysis thus suggests that institutions evolve in response to changing environmental conditions but in ways constrained by past trajectories.
Stable topological transitivity properties of ℝn-extensions of hyperbolic transformations
Authors: MOSS A. , WALKDEN C. P.
Published: June 2011

We consider ℝn skew-products of a class of hyperbolic dynamical systems. It was proved by Niţică and Pollicott [Transitivity of Euclidean extensions of Anosov diffeomorphisms. Ergod. Th. & Dynam. Sys. 25 (2005), 257–269] that for an Anosov diffeomorphism ϕ of an infranilmanifold Λ there is (subject to avoiding natural obstructions) an open and dense set f:Λ→ℝN for which the skew-product ϕf(x,v)=(ϕ(x),v+f(x)) on Λ×ℝN has a dense orbit. We prove a similar result in the context of an Axiom A hyperbolic flow on an attractor.
On Hilbert dynamical systems
Authors: GLASNER ELI , WEISS BENJAMIN
Published: June 2011

Returning to a classical question in harmonic analysis, we strengthen an old result of Walter Rudin. We show that there exists a weakly almost periodic function on the group of integers ℤ which is not in the norm-closure of the algebraB(ℤ) of Fourier–Stieltjes transforms of measures on the dual group$\hat {\mathbb {Z}}=\mathbb {T}$, and which isrecurrent. We also show that there is a Polish monothetic group which is reflexively but not Hilbert representable.
Lifecourse determinants and incomes in retirement: Belgium and the United Kingdom compared
Authors: DEWILDE CAROLINE
Published: June 2011

In this paper, the impact of lifecourse family and labour market experiences on household incomes of older people in Belgium and the United Kingdom (UK) is analysed. To this end, panel data and life-history information from the Panel Study of Belgian Households and the British Household Panel Survey are combined. The results show that old-age income is indeed influenced by previous lifecourse experiences, and that differences between Belgium and the UK can be explained in terms of (the development over time of) welfare regime arrangements. Family experiences have a larger impact on old-age incomes in ‘male-breadwinner’ Belgium, while in Britain labour market events are more important. As social transfers in Britain are more aimed at poverty prevention and less at income replacement, a ‘scarring effect’ of unemployment persists even into old age. Also, the more of one's career is spent in blue-collar work or self-employment/farming, the lower the income in old age. A new finding is that, notwithstanding the high level of ‘de-commodification’ achieved by the Belgian welfare state, this effect turns out to be significantly stronger in Belgium than in the UK. Compared to the market, the welfare state is hence a more efficient ‘mechanism’ of stratification for incomes in old age.
Determinants of household contributions to collective irrigation management: The case of the Doho Rice Scheme in Uganda
Authors: NAKANO YUKO , OTSUKA KEIJIRO
Published: June 2011

In order to explore the conditions for successful communal irrigation management, this study investigates the determinants of household contributions to the cleaning of irrigation channels and the availability of water. By using household-level data collected in a large-scale gravity irrigation scheme in Uganda, whose management was transferred from the government to the community, we find that household contributions to the cleaning of irrigation channels are determined by the scarcity of irrigation water, the opportunity cost of labor and the private benefit associated with plot size. We also find that the availability of irrigation water increases in the tertiary irrigation canal where the coefficient of variation of plot size is large, which may indicate that farmers of larger plots are particularly active in water management. These findings suggest that farmers are responsive to private benefits and, hence, the support of the government for communities to implement punishment may be effective for successful irrigation management.
Ecological functions and economic value of the Neotropic Cormorant (Phalacrocorax brasilianus) in Los Olivitos Estuary, Venezuela
Authors: GIL-WEIR KARINE , WEIR ENRIQUE , CASLER CLARK L. , ANIYAR SARA
Published: June 2011

We present the ecological functions of cormorants and estimate the economic value of these functions to artisanal fishermen, as a valuation exercise for Neotropic Cormorants at Los Olivitos Estuary, Lake Maracaibo, Venezuela. Ecological functions were based on estimating the abundance, distribution and diet of cormorants; economic values were attached to a selection of goods, services and attributes. Based on available information, we selected four ecological–economic functions of cormorants: harvesting for food; contributors to fish diversity; indicators of fish schools; and contributors to fish biomass, due to guano production. Cormorants consumed nine commercial fish species. Mean consumption was 225 g/ind/day. All ecological–economic functions were positive except for the role as contributors to fish biomass. Total value of the cormorant population to fishermen was $5,429,703/year. Unlike many studies, our results show that Neotropic Cormorants have a negligible impact on artisanal fisheries. We emphasize the importance of these results for management policies.
What's in the lunchbox? Dietary behaviour of learners from disadvantaged schools in the Western Cape, South Africa
Authors: Abrahams Zulfa , de Villiers Anniza , Steyn Nelia P , Fourie Jean , Dalais Lucinda , Hill Jillian , Draper Catherine E , Lambert Estelle V
Published: June 2011

Objective

To identify and describe factors associated with food shop (known as tuck shop in South Africa) and lunchbox behaviours of primary-school learners in South Africa.

Design

Analysis of data collected in 2008 from a cross-sectional survey.

Setting

Sixteen primary schools in the Western Cape, South Africa.

Subjects

A total of 717 grade 4 learners aged 10–12 years.

Results

A 24 h recall established that 69 % of learners carried a lunchbox to school and 49 % had consumed at least one item purchased from the school food shop/vendor. Most lunchboxes contained white bread with processed meat, whereas the most frequent food shop/vendor purchase comprised chips/crisps. Learners who carried a lunchbox to school had significantly lower BMI percentiles (P= 0·002) and BMI-for-age (P= 0·034), compared with their counterparts. Moreover, they were younger, had higher standard-of-living and dietary diversity scores, consumed more meals per day, had greater self-efficacy and came from predominantly urban schools, compared with those who did not carry a lunchbox to school. Learners who ate food shop/vendor purchases had a lower standard-of-living score and higher dietary diversity and meal scores. Only 2 % of learners were underweight, whereas 19 % were stunted and 21 % were overweight/obese (BMI ≥ 25 kg/m2).

Conclusions

Children who carried a lunchbox to school appeared to have greater dietary diversity, consumed more regular meals, had a higher standard of living and greater nutritional self-efficacy compared with those who did not carry a lunchbox to school.
Characters and growth of admissible representations of reductive p-adic groups
Authors: Meyer Ralf , Solleveld Maarten
Published: June 2011

We use coefficient systems on the affine Bruhat–Tits building to study admissible representations of reductive p-adic groups in characteristic not equal to p. We show that the character function is locally constant and provide explicit neighbourhoods of constancy. We estimate the growth of the subspaces of invariants for compact open subgroups.
Algeria, France, Mexico, UNESCO: a transnational history of anti-racism and decolonization, 1932–1962
Authors: Shepard Todd
Published: June 2011

Two crucial terms in discussions about racial or ethnic relations – ‘discrimination’ and ‘integration’ – first appeared in official French documents in the 1950s. They quickly became key references in the government’s pioneering efforts, in response to the Algerian revolution, to recognize the importance and fight against the effects of French racism on ‘Muslim French citizens from Algeria’. This policy was named ‘integrationism’; its premises and measures had overseas inspirations and it was bureaucrats from an international organization who made such policy models available for French adoption. All of this was possible because of transnational networks of social scientists, which included some who helped author them as well as others who studied and wrote about them. More specifically, it was projects and claims from Mexico that provided the most direct references for French integrationist policies and it was through the efforts of UNESCO that French integrationists gained detailed knowledge about them.
The difficult task of predicting the costs of community-based mental health care. A comprehensive case register study
Authors: Donisi V. , Jones J. , Pertile R. , Salazzari D. , Grigoletti L. , Tansella M. , Amaddeo F.
Published: June 2011

Background.

Previous studies have attempted to forecast the costs of mental health care, using clinical and individual variables; the inclusion of ecological measures could improve the knowledge of predictors of psychiatric service utilisation and costs to support clinical and strategic decision-making.

Methods.

Using a Psychiatric Case Register (PCR), all patients with an ICD-10 psychiatric diagnosis, who had at least one contact with community-based psychiatric services in the Verona Health District, Northern Italy, were included in the study (N = 4558). For each patient, one year's total cost of care was calculated by merging service contact data with unit cost estimates and clinical and socio-demographic variables were collected. A socio-economic status (SES) index was developed, as a proxy of deprivation, using census data. Multilevel multiple regression models, considering socio-demographic and clinical characteristics of patients as well as socioeconomic local characteristics, were estimated to predict costs.

Results.

The mean annual cost for all patients was 2,606.11 Euros; patients with an ongoing episode of care and with psychosis presented higher mean costs. Previous psychiatric history represented the most significant predictor of cost (36.99%R2increase) and diagnosis was also a significant predictor but explained only 4.96% of cost variance. Psychiatric costs were uniform throughout the Verona Health District and SES characteristics alone contributed towards less than 1% of the cost variance.

Conclusions.

For all patients of community-based psychiatric services, a comprehensive model, including both patients' individual characteristics and socioeconomic local status, was able to predict 43% of variance in costs of care.
Should we assess climate model predictions in light of severe tests?
Authors: Katzav Joel
Published: June 2011

According to Austro‐British philosopher Karl Popper, a system of theoretical claims is scientific only if it is methodologically falsifiable, i.e., only if systematic attempts to falsify or severely test the system are being carried out [Popper, 2005, pp. 20, 62]. He holds that a test of a theoretical system is severe if and only if it is a test of the applicability of the system to a case in which the system's failure is likely in light of background knowledge, i.e., in light of scientific assumptions other than those of the system being tested [Popper, 2002, p. 150]. Popper counts the 1919 tests of general relativity's then unlikely predictions of the deflection of light in the Sun's gravitational field as severe. An implication of Popper's above condition for being a scientific theoretical system is the injunction to assess theoretical systems in light of how well they have withstood severe testing. Applying this injunction to assessing the quality of climate model predictions (CMPs), including climate model projections, would involve assigning a quality to each CMP as a function of how well it has withstood severe tests allowed by its implications for past, present, and nearfuture climate or, alternatively, as a function of how well the models that generated the CMP have withstood severe tests of their suitability for generating the CMP.
Standardizing experiments in geoengineering
Authors: Robock Alan , Kravitz Ben , Boucher Olivier
Published: June 2011

GeoMIP Stratospheric Aerosol Geoengineering Workshop; New Brunswick, New Jersey, 10–12 February 2011; The term “geoengineering” refers to deliberate large‐scale anthropogenic modification of the climate. The most frequently discussed type of geoengineering, using socalled solar radiation management (SRM) to counteract global warming, has been to try to create a stratospheric aerosol cloud to reflect solar radiation. Stratospheric aerosols have the potential to cool the planet within a few years, as demonstrated by large natural volcanic eruptions. If a stratospheric aerosol layer could be maintained artificially, it could reduce or reverse some of the impacts of climate change, such as ice sheet melting, sea level rise, and thawing of permafrost.
Quantifying the coastal contribution to the North American carbon budget
Authors: Benway Heather M.
Published: June 2011

A Coastal Interim Synthesis Workshop; San Francisco, California, 11–12 December 2010; The contribution of coastal margins to regional and global carbon budgets is poorly constrained, largely due to limited information about the magnitude, spatial distribution, and temporal variability of carbon sources and sinks in coastal waters. Building on recommendations of the 2005 North American Continental Margins (NACM) Synthesis and Planning Workshop (http://www.us‐ocb.org/publications/NACM small.pdf), the Ocean Carbon and Biogeochemistry (OCB) program (http://www.us‐ocb.org) is collaborating with the North American Carbon Program (NACP) on a Coastal Interim Synthesis activity to compile observational and modeling results on carbon cycle fluxes along the North American continental margins. This activity is divided into five regions: East Coast, West Coast, Gulf of Mexico, Arctic, and Great Lakes. A coastal synthesis workshop, coordinated by OCB and NACP and sponsored by NASA, convened 56 participants.
Climate Change and Climate Modeling
Authors: Schmidt Gavin
Published: June 2011

In long‐established fields like fluid mechanics or quantum theory, the contents of introductory textbooks are mostly predictable: The basics are covered in more or less the same order, and while cutting‐edge research occasionally gets a look‐in (depending on the inclinations of the authors), the contents are far more frequently reworkings of previous textbooks than a synthesis of recent primary literature. In a field like climate science, however, where there is a much shorter history of textbook writing, much of the subject matter is extracted directly from papers published in the past 10 years. This makes the resulting textbooks far more varied and interesting.
Carbon in Earth's core
Authors: Tretkoff Ernie
Published: June 2011

The Earth's dense core consists primarily of iron, but seismological data and mineral physics results show that the inner core is lighter than pure iron by 3–7% and the outer core is lighter than pure iron by 5–10%. Therefore, the core must also contain some lighter element. One possible light element is carbon, which readily forms alloys with iron and is abundant in the universe. Geochemical studies also suggest that carbon is present, but it is uncertain how much carbon is in the core or what form it is in. (Journal of Geophysical Research‐Solid Earth, doi:10.1029/2010JB007819, 2011)
The correlation between electric field emission phenomenon and Schottky contact reverse bias characteristics in nanostructured systems
Authors: Yu J. , Liu J. , Breedon M. , Shafiei M. , Wen H. , Li Y. X. , Wlodarski W. , Zhang G. , Kalantar-zadeh K.
Published: June 2011

Two different morphologies of nanotextured molybdenum oxide were deposited by thermal evaporation. By measuring their field emission (FE) properties, an enhancement factor was extracted. Subsequently, these films were coated with a thin layer of Pt to form Schottky contacts. The current-voltage (I-V) characteristics showed low magnitude reverse breakdown voltages, which we attributed to the localized electric field enhancement. An enhancement factor was obtained from the I-V curves. We will show that the enhancement factor extracted from the I-V curves is in good agreement with the enhancement factor extracted from the FE measurements.
Simulation of multiple ordered phases in C23 n-alkane
Authors: Wentzel Nathaniel , Milner Scott T.
Published: June 2011

Normal alkanes display multiple ordered phases, including an orthorhombic crystal (X) and two partially ordered rotator phases (RI and RII). The rotator phase transitions X–RI and RI–RII are of interest because they are weakly first-order, and because experiments suggest that crystalline polyethylene may nucleate via a metastable rotator phase. We have performed heating and cooling scans of all-atom NσT (isothermal, isostress) simulations of a pure C23 solid. We find a sequence of phases, transition temperatures, structural and thermodynamic properties, all reasonably consistent with experiment, except that a monoclinic crystal is more stable in our simulations than the experimental orthorhombic structure. We find that the RI phase is well described as an orthorhombic crystal disordered by random ±90° rotations of molecules about their stem axis, and the RII phase can be represented as a loose hexagonal packing of parallel chain stems, which tend to orient with the in-plane projection of C-C bonds pointing between neighbors. To measure local orthorhombic, RI, or RII order, we define Potts- and Ising-like order parameters, from which global order parameters and correlation functions can be computed. We observe modest pretransitional fluctuations of local RI order in the RII phase near TRI-RII, characteristic of this weakly first-order transition.
Dynamics of zero-Prandtl number convection near onset
Authors: Paul Supriyo , Pal Pinaki , Wahi Pankaj , Verma Mahendra K.
Published: June 2011

We present a detailed bifurcation scenario of zero-Prandtl number Rayleigh-Bénard convection using direct numerical simulations (DNS) and a 27-mode low-dimensional model containing the most energetic modes of DNS. The bifurcation analysis reveals a rich variety of convective flow patterns and chaotic solutions, some of which are common to that of the 13-mode model of Pal et al. [EPL 87, 54003 (2009)]. We also observed a set of periodic and chaotic wavy rolls in DNS and in the model similar to those observed in experiments and numerical simulations. The time period of the wavy rolls is closely related to the eigenvalues of the stability matrix of the Hopf bifurcation points at the onset of convection. This time period is in good agreement with the experimental results for low-Prandtl number fluids. The chaotic attractor of the wavy roll solutions is born through a quasiperiodic and phase-locking route to chaos.
Hydrogenated amorphous silicon oxide containing a microcrystalline silicon phase and usage as an intermediate reflector in thin-film silicon solar cells
Authors: Lambertz A. , Grundler T. , Finger F.
Published: June 2011

To further improve the stability of amorphous/microcrystalline silicon (a-Si:H/μc-Si:H) tandem solar cells, it is important to reduce the thickness of the a-Si:H top cell. This can be achieved by introduction of an intermediate reflector between the a-Si:H top and the μc-Si:H bottom cell which reflects light back into the a-Si:H cell and thus, increases its photocurrent at possibly reduced thickness. Microcrystalline silicon oxide (μc-SiOx:H) is used for this purpose and the trade-off between the material’s optical, electrical and structural properties is studied in detail. The material is prepared with plasma enhanced chemical vapor deposition from gas mixtures of silane, carbon dioxide and hydrogen. Phosphorus doping is used to make the material highly conductive n-type. Intermediate reflectors with different optical and electrical properties are then built into tandem solar cells as part of the inner n/p-recombination junction. The quantum efficiency and the reflectance of these solar cells are evaluated to find optical gains and losses due to the intermediate reflector. Suitable intermediate reflectors result in a considerable increase in the top cell current density which allows a reduction of the a-Si:H top cell thickness of about 40% for a tandem cell while keeping the current density of the device constant.
Local electrical stress-induced doping and formation of monolayer graphene P-N junction
Authors: Yu Tianhua , Liang Chen-Wei , Kim Changdong , Yu Bin
Published: June 2011

We demonstrated doping in monolayer graphene via local electrical stressing. The doping, confirmed by the resistance-voltage transfer characteristics of the graphene system, is observed to continuously tunable from N-type to P-type as the electrical stressing level (voltage) increases. Two major physical mechanisms are proposed to interpret the observed phenomena: modifications of surface chemistry for N-type doping (at low-level stressing) and thermally-activated charge transfer from graphene to SiO2 substrate for P-type doping (at high-level stressing). The formation of P-N junction on two-dimensional graphene monolayer is demonstrated with complementary doping based on locally applied electrical stressing.
A comparison of Vlasov with drift kinetic and gyrokinetic theories
Authors: Tasso H. , Throumoulopoulos G. N.
Published: June 2011

A kinetic consideration of an axisymmetric equilibrium with vanishing electric field near the magnetic axis shows that ∇f should not vanish on axis within the framework of Vlasov theory while it can either vanish or not in the framework of both a drift kinetic and a gyrokinetic theories (f is either the pertinent particle or the guiding center distribution function). This different behavior, relating to the reduction of phase space which leads to the loss of a Vlasov constant of motion, may result in the construction of different currents in the reduced phase space than the Vlasov ones. This conclusion is indicative of some limitation on the implications of reduced kinetic theories, in particular, as concerns the physics of energetic particles in the central region of magnetically confined plasmas.
Thermal conductivity depth-profile reconstruction of multilayered cylindrical solids using the thermal-wave Green function method
Authors: Xie Guangxi , Zhang Jie , Liu Liwang , Wang Chinhua , Mandelis Andreas
Published: June 2011

In this paper, a theoretical model for characterizing solid multi-layered cylindrical samples illuminated by a modulated uniform incident beam is developed by means of the Green function method. The specific Green function for the multi-layered cylindrical structure is derived and an analytical expression for the thermal-wave field in such a cylindrical sample is presented. The thermal-wave field of an inhomogeneous cylindrical sample irradiated with incident light of arbitrary angular and/or radial intensity distribution was obtained using this theoretical model. Furthermore, experimental validation is also presented in the form of experimental results with steel cylinders of various diameters.
Fabrication and characterization of extended arrays of Ag2S/Ag nanodot resistive switches
Authors: Wang Daoai , Liu Lifeng , Kim Yunseok , Huang Zhipeng , Pantel Daniel , Hesse Dietrich , Alexe Marin
Published: June 2011

Well-ordered Ag2S/Ag nanodot arrays with a density of >60 Gbit/in.2 have been fabricated by sputtering Ag on a silicon substrate using ultrathin porous anodic aluminum oxide membranes as shadow masks, followed by sulfurization treatment at room temperature. The morphology, microstructure, and electrical properties of the as-prepared nanodots were characterized by scanning electron microscopy, x-ray diffractometry, transmission electron microscopy, and conductive atomic force microscopy, respectively. Well-defined resistive switching behavior was observed in these nanodots, and the ON/OFF ratio was found to be higher than 102. The Ag2S/Ag nanodot arrays hold substantial promise for use as ultrahigh density nonvolatile memory devices.
Self-aligned epitaxial metal-semiconductor hybrid nanostructures for plasmonics
Authors: Urbańczyk Adam , van Otten Frank W. M. , Nötzel Richard
Published: June 2011

We demonstrate self-alignment of epitaxial Ag nanocrystals on top of low-density near-surface InAs quantum dots (QDs) grown by molecular beam epitaxy. The Ag nanocrystals support a surface plasmon resonance that can be tuned to the emission wavelength of the QDs. Photoluminescence measurements of such hybrid metal-semiconductor nanostructures reveal large enhancement of the emission intensity. Our concept of epitaxial self-alignment enables the integration of plasmonic functionality with electronic and photonic semiconductor devices operating down to the single QD level.
Magnetocrystalline anisotropy of magnetic grains in Co80Pt20:oxide thin films probed by x-ray magnetic circular dichroism
Authors: Zhang W. , Morton S. A. , Wong P. K. J. , Hu X. F. , Arenholz E. , Lu B. , Cheng T. Y. , Xu Y. B. , van der Laan G.
Published: June 2011

Using angle-dependent x-ray magnetic circular dichroism, we have measured magnetic hysteresis loops at the Co L2,3 edges of oxide-doped Co80Pt20 thin films. The magnetocrystalline anisotropy energy (MAE) of the Co atoms, which is the main source of the magnetocrystalline anisotropy of the CoPt magnetic grains, has been determined directly from these element-specific hysteresis loops. When the oxide volume fraction (OVF) is increased from 16.6% to 20.7%, the Co MAE has been found to decrease from 0.117 meV/atom to 0.076 meV/atom. While a larger OVF helps one to achieve a smaller grain size, it reduces the magnetocrystalline anisotropy, as demonstrated unambiguously from the direct Co MAE measurements. Our results suggest that those Co80Pt20:oxide films with an OVF between 19.1% and 20.7% are suitable candidates for high-density magnetic recording.
Self-aligned metal source/drain InP n-metal-oxide-semiconductor field-effect transistors using Ni–InP metallic alloy
Authors: Kim SangHyeon , Yokoyama Masafumi , Taoka Noriyuki , Iida Ryo , Lee Sunghoon , Nakane Ryosho , Urabe Yuji , Miyata Noriyuki , Yasuda Tetsuji , Yamada Hisashi , Fukuhara Noboru , Hata Masahiko , Takenaka Mitsuru , Takagi Shinichi
Published: June 2011

In this work, we report that a Ni–InP alloy can be used as a source/drain (S/D) metal for InP metal-oxide-semiconductor field-effect transistors (MOSFETs), allowing us to employ the salicidelike self-align S/D formation. Ni–InP alloys have low sheet resistance under 100 Ω/◻ and Ni can be selectively etched without etching of Ni–InP. We also demonstrate operation of the metal S/D InP MOSFETs using Ni–InP alloy. The InP MOSFETs exhibit high Ion/Ioff ratio of 106 and low subthreshold swing of 101 mV/dec.
The no-binding regime of the Pauli-Fierz model
Authors: Hiroshima Fumio , Spohn Herbert , Suzuki Akito
Published: June 2011

The Pauli-Fierz model H(α) in nonrelativistic quantum electrodynamics is considered. The external potential V is sufficiently shallow and the dipole approximation is assumed. It is proven that there exist constants 0 < α− < α+ such that H(α) has no ground state for |α| < α−, which complements an earlier result stating that there is a ground state for |α| > α+. We develop a suitable extension of the Birman-Schwinger argument. Moreover, for any given δ > 0 examples of potentials V are provided such that α+ − α− < δ.
Improving polymer solar cell performances by manipulating the self-organization of polymer
Authors: Xie Feng-xian , Choy Wallace C. H. , Zhu Xiaolong , Li Xiaolong , Li Zhong , Liang Chunjun
Published: June 2011

We have investigated driving force effects on the ordering of polymer, which is a key factor of self-assembly of soft materials. By turning the substrate up-side-down, the downward driving force can form in solution film-growth process and affect the self-organization of polymer chains and domains. We introduce Brown’s capillarity theory [J. Polym. Sci., Polym. Phys. Ed. 22, 423 (1956)] to describe the film formation. Our results show that the better chain and lamellae packing of polymer make hole transport, carrier balance, and power conversion efficiency of annealed and unannealed devices improve even with thick active-layers as compared to conventional devices.
Epitaxial growth of high mobility Bi2Se3 thin films on CdS
Authors: Kou X. F. , He L. , Xiu F. X. , Lang M. R. , Liao Z. M. , Wang Y. , Fedorov A. V. , Yu X. X. , Tang J. S. , Huang G. , Jiang X. W. , Zhu J. F. , Zou J. , Wang K. L.
Published: June 2011

We report the experiment of high quality epitaxial growth of Bi2Se3 thin films on hexagonal CdS (0001) substrates using a solid source molecular-beam epitaxy system. Layer-by-layer growth of single crystal Bi2Se3 has been observed from the first quintuple layer. The size of surface triangular terraces has exceeded 1 μm. Angle-resolved photoemission spectroscopy clearly reveals the presence of Dirac-cone-shape surface states. Magneto-transport measurements demonstrate a high Hall mobility of ∼6000 cm2/V s for the as-grown Bi2Se3 thin films at temperatures below 30 K. These characteristics of Bi2Se3 thin films promise a variety of potential applications in ultrafast, low-power dissipation devices.
Surface roughening evolution in pentacene thin film growth
Authors: Zhu H. , Li Q. L. , She X. J. , Wang S. D.
Published: June 2011

We report investigation on the surface roughening evolution during the pentacene thin film growth, and it turns out to be the overall hopping-up mass transport from the under layers to the upper layers responsible for the surface roughening. A simple interlayer mass transport model utilizing a roughness evolution ratio has been developed, based on which the extent of the interlayer mass transport is found to be reduced with the film thickness. The surface roughening mechanism is considered to be associated with the gradual phase change with the film thickness due to the pentacene polymorphism.
SmNiO
3
/
NdNiO
3
thin film multilayers
Authors: Girardot C. , Pignard S. , Weiss F. , Kreisel J.
Published: June 2011

Rare earth nickelates RENiO3 (RE=rare earth), which attract interest due to their sharp metal-insulator phase transition, are instable in bulk form due to the necessity of an important oxygen pressure to stabilize Ni in its 3+ state of oxidation. Here, we report the stabilization of RE nickelates in [(SmNiO3)t/(NdNiO3)t]n thin film multilayers, t being the thickness of layers alternated n times. Both bilayers and multilayers have been deposited by metal-organic chemical vapor deposition. The multilayer structure and the presence of the metastable phases SmNiO3 and NdNiO3 are evidenced from by x-ray and Raman scattering. Electric measurements of a bilayer structure further support the structural quality of the embedded RE nickelate layers.
Hot electron injection effect on the microwave performance of type-I/II AlInP/GaAsSb/InP double-heterojunction bipolar transistors
Authors: Cheng K. Y. Donald , Liao C. C. , Xu H. , Cheng K. Y. Norman , Feng M.
Published: June 2011

A type-I/II double heterojunction bipolar transistor (DHBT) with a layer structure of AlInP(emitter)/GaAsSb(composition graded base)/InP(collector) was designed and grown by molecular beam epitaxy technique. The band alignment of the type-I AlInP/GaAsSb emitter-base interface provides hot electron injection into the base to enhance the effective base velocity to 2.54×107 cm/s, resulting in an improved device gain and high frequency performance. We have fabricated a submicron emitter (AE=0.35×4 μm2) type-I/II DHBT with a demonstrated current gain of β=50 and a breakdown voltage of BVCEO=4.2 V, with a cutoff frequency of fT=455 GHz and fMAX=400 GHz at a collector current density, JC=10 mA/μm2.
Electronic structure and optical properties of 2,5,8,11-tetra-tert-butylperylene polyhedral crystals from x-ray absorption near-edge structure and x-ray excited optical luminescence studies
Authors: Lv Jingyu , Ko Peter J. Y. , Zhang Ying , Liu Lijia , Zhang Xiujuan , Zhang Xiaohong , Sun Xuhui , Sham T. K.
Published: June 2011

X-ray absorption near-edge structure (XANES) and x-ray excited optical luminescence (XEOL) have been used to study the optical properties of 2,5,8,11-tetra-tert-butylperylene (TBPe) polyhedral crystals with morphology varies from cube to rhombic dodecahedron. Benefit from the high resolution of synchrotron radiation spectroscopy, C 1s to π∗ and σ∗ transitions from different carbon sites in TBPe can be clearly distinguished in the carbon K-edge XANES. XEOL studies reveal that different crystals exhibit multiple emission bands with different branching ratio. It is also found that all the polyhedral crystals exhibit a weak luminescence in the near infrared, which is absent in the powder sample.
Optical field-enhancement in metal nanoparticle arrays contacted by electron beam induced deposition
Authors: Mangold M. A. , Weiss C. , Dirks B. , Holleitner A. W.
Published: June 2011

We study the impact of optical field-enhancement effects on the optoelectronic properties of metal nanoparticle arrays. Applying a focused ion beam lithography in combination with an electron beam induced deposition technique we pattern electrical contacts in a way that they give rise to an electromagnetic field-enhancement. The field-enhancement is directly observed in an enhanced photoconductance of the arrays. Finite-difference time-domain simulations verify that an antenna effect is responsible for the observed increase in the photoconductance.
An atmospheric pressure quasiuniform planar plasma jet generated by using a dielectric barrier configuration
Authors: Li Qing , Takana Hidemasa , Pu Yi-Kang , Nishiyama Hideya
Published: June 2011

A stable nonthermal quasiuniform planar plasma jet, originating from a planar dielectric duct with a rectangular exit and issuing into ambient air at atmospheric pressure, is reported in the present work. Current-voltage characteristics, one discharge current pulse per sinusoidal half voltage cycle, show that the discharge is not filamentary. Its spatial uniformity in the transverse direction is shown to be excellent by monitoring optical emission spectra in the jet core region except jet boundaries. This is possibly resulted from high preionization in the upstream region, and it is a challenge to the traditional single streamer explanation for nonthermal plasma jets.
Field emission cooling of thermoelectric semiconductor PbTe
Authors: Chung M. S. , Mayer A. , Weiss B. L. , Miskovsky N. M. , Cutler P. H.
Published: June 2011

We report a theoretical analysis of the cooling effect due to field emission from n-type PbTe, a typical thermoelectric material. We show that, by calculating the average energies of field and replacement electrons, the energy exchange in field emission from n-type PbTe always produces cooling. The resultant heat loss leads to cooling of up to a few tenths of an electron volt per field emitted electron. For n-type PbTe, the Nottingham energy exchange in field emission can be comparable to or greater than the Peltier coefficient.
Note: Study of extreme ultraviolet and soft x-ray emission of metal targets produced by laser-plasma-interaction
Authors: Mantouvalou I. , Jung R. , Tuemmler J. , Legall H. , Bidu T. , Stiel H. , Malzer W. , Kanngießer B. , Sandner W.
Published: June 2011

Different metal targets were investigated as possible source material for tailored laser-produced plasma-sources. In the wavelength range from 1 to 20 nm, x-ray spectra were collected with a calibrated spectrometer with a resolution of λ/Δλ = 150 at 1 nm up to λ/Δλ = 1100 at 15 nm. Intense line emission features of highly ionized species as well as continuum-like spectra from unresolved transitions are presented. With this knowledge, the optimal target material can be identified for the envisioned application of the source in x-ray spectrometry on the high energy side of the spectra at about 1 keV. This energy is aimed for because 1 keV-radiation is ideally suited for L-shell x-ray spectroscopy with nm-depth resolution.
The adsorption and co-adsorption of oxygen and carbon monoxide on Pt3Ni(111): A vibrational study
Authors: Chiarello G. , Marino A. R. , Formoso V. , Politano A.
Published: June 2011

High-resolution electron energy loss spectroscopy has been used to investigate the adsorption and co-adsorption of oxygen and CO on the Pt3Ni(111) surface. For the sake of comparison, similar measurements have also been performed on the Pt(111) surface. We find that CO adsorbs at the same manner on both surfaces. By contrast, significant differences between the two surfaces exist concerning the adsorption of O and the co-adsorption of O with CO.
Ni induced few-layer graphene growth at low temperature by pulsed laser deposition
Authors: Wang K. , Tai G. , Wong K. H. , Lau S. P. , Guo W.
Published: June 2011

We have used pulsed laser deposition to fabricate graphene on catalytic nickel thin film at reduced temperature of 650 °C. Non-destructive micro-Raman spectroscopic study on our samples, measuring 1x1 cm2 each, has revealed few-layer graphene formation. Bi-, tri-, and few-layer graphene growth has been verified by High Resolution Transmission Electron Microscopy. Our experimental results imply that the number of graphene layers formation relies on film thickness ratios of C to Ni, which can be well controlled by varying the laser ablation time. This simple and low temperature synthesizing method is excellent for graphene based nanotechnology research and device fabrication.