bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transport properties of heterostructures
Authors: Balkanski M , Wallis R F 
Published: November 2023

Abstract
There are two aspects of heterostructures contammg two-dimensional systems that make their transport properties significantly different from those of three-dimensional structures. First, heterostructures have a large anisotropy of their transport properties in the directions parallel and perpendicular to the growth axis. Second, much higher mobilities can be achieved in such structures.
Symmetries in Quantum Mechanics
Authors: Stancu Fl 
Published: November 2023

Abstract
Group theory is a branch of mathematics appropriate for studying symmetries of physical systems. A symmetry is a natural attribute of the physical world and therefore is the starting point of any physical law. The foundation of dynamics is in Lagrangian theory or equivalently in Hamiltonian theory. A symmetry of a physical system is expressed by the invariance of its Lagrangian or Hamiltonian, or ultimately of its equations of motion, under certain transformations. When these transformations form groups it is convenient and useful to study symmetries through group theory. Group theory can explain observed regularities and helps to simplify and unify the physics of apparently different systems. It is a valuable tool that helps in predicting the behaviour of systems for which a symmetry has been found.
The rectilinear ascent and descent of bodies
Authors: Chandrasekhar S 
Published: November 2023

Abstract
This is an inversion of the common procedure: rectilinear motion in a central field of force is generally (if not always) considered as a special (and a simpler) case that requires a separate treatment since the angular momentum of such motions is zero and there is no constant of areas as a (non-trivial) constraint. Instead, Newton considers rectilinear motion as a limiting case of motion along conic sections and shows how it becomes determinate by an ‘invariant’ form of the law of areas which applies to orbits independently of their eccentricity.
The conservation of energy and the initial-value problem
Authors: Chandrasekhar S 
Published: November 2023

Abstract
Section VIII, including three Propositions XL, XLI, and XLII, represents a watershed in the development of the Principia: it completes the treatment of ‘the motion of bodies in immovable orbits’. But it is very much more than that: in deriving the energy integral (and implicitly the notion of potential energy) and in formulating and solving the initial-value problem in the framework of his dynamics, Newton established for the first time two of the basic tenets of physics. Newton must have been fully aware of the significance of these propositions. But his presentation of them manifests a strange impatience-of this later! Meantime, it will suffice to remark that superficially, Propositions XLI and XLII are presented as straightforward generalizations of Proposition XXXIX and its corollary. And there are, of course, examples of his insight and his craftsmanship.
The two-body problem
Authors: Chandrasekhar S 
Published: November 2023

Abstract
As we have stated in the introduction to the last chapter (§57), a watershed was reached in the development of the Principia at the end of Section IX. In resuming the main development, after a brief pause in Section X, Newton writes: I have hitherto been treating of the attractions of bodies towards an immovable centre; though very probably there is no such thing existent in nature. For attractions are made towards bodies, and the actions of the bodies attracted and attracting are always reciprocal and equal, by Law m; so that if there are two bodies, neither the attracted nor the attracting body is truly at rest, but both (by CoR. IV of the Laws of Motion), being as it were mutually attracted, revolve about a common centre of gravity. And if there be more bodies, which either are attracted by one body, which is attracted by them again, or which all attract each other mutually, these bodies will be so moved among themselves, that their common centre of gravity will either be at rest, or move uniformly forwards in a right line. I shall therefore at present go on to treat of the motion of bodies attracting each other; considering the centripetal forces as attractions; though perhaps in a physical strictness they may more truly be called impulses. But these propositions are to be considered as purely mathematical; and therefore, laying aside all physical considerations, I make use of a familiar way of speaking, to make myself the more easily understood by a mathematical reader.
Attraction by non-spherical bodies
Authors: Chandrasekhar S 
Published: November 2023

Abstract
As Newton stated in his concluding Scholium of Proposition LXXXIV, his next concern was the attraction by non-spherical bodies; but ‘to treat them particularly was not his design’. Even so, Propositions LXXXVII and Corollaries II and III of Proposition XCI stand out. In Proposition LXXXVII, Newton establishes a scaling law for the force exerted at an external point by an arbitrary distribution of mass specified by a density function and the law of centripetal attraction, by the elements of mass of the distribution, is inversely as the nth power of the distance.
On the theory of tides
Authors: Chandrasekhar S 
Published: November 2023

Abstract
But among all the great men who have philosophized about this remarkable effect, I am more astonished at Kepler than at any other. Despite his open and acute mind, and though he has at his fingertips the motions atributed to the earth, he has nevertheless lent his ear and his assent to the moon’s dominion over the waters, to occult properties, and to such puerilities. Concerning the Cause of the tides given by M. Newton, I am by no means satisfied by it, nor by all other Theories that he builds upon his principle of Attraction, which to me seems absurd, ... And I have often wondered how he could have given himself all the trouble of making such a number of investigations and difficult calculations that have no other foundation than this very principle.
The velocity of sound and of long waves in canals
Authors: Chandrasekhar S 
Published: November 2023

Abstract
One can search in vain to find an adequate account of Newton’s investigations on the velocity of sound in Propositions XLVII-XL of Book II. The best that I have been able to find (which is not saying very much in the context) is that of Rayleigh’s:* The first theoretical investigation of the velocity of sound was made by Newton, who assumed that the relation between pressure and density was that formulated in Boyle’s law.
The diatomic molecule
Authors: Sutton Adrian P 
Published: November 2023

Abstract
In this section we shall review some of the mathematical ideas you should have been exposed to in a course on quantum mechanics. If you find that you still do not understand the material described in this section and would like to read more, I suggest you try Chapter 8 of Feynman et al. (1966). It looks weird at first but it is really very simple. You just have to become familiar with it through using it and solving problems. Before we get into quantum mechanics let us take a fresh look at something that we are already familiar with and which is closely related to the mathematics we need to develop, namely vectors. A vector is something that has both magnitude and direction.
Structural stability of compounds
Authors: Sutton Adrian P 
Published: November 2023

Abstract
The notion that particular atomic configurations of molecules and crystals are stabilized by the formation of bonds between particular hybrid states assumes the bonds are saturated, that is, occupied by two electrons each. For example, in our earlier discussion of sp hybrids we assumed that each bond was occupied by two electrons. A saturated single C-C bond has a characteristic length and energy which is almost independent of the types of other atoms bonded to the two C atoms. The properties of a C-C bond depend on the configuration of atoms in the local environment because the configuration determines whether the C-C bond is a single, double, or triple bond. But for a given number and angular disposition of bonds to each C atom the C-C bond is less sensitive to whether other C or H or 0, etc. atoms are bonded to the two C atoms. This is the basis of ‘covalent radii’ for atoms in characteristic bonding topologies. It is as if each saturated bond has a personalized local wave function and properties. In valence bond theory this is known as the ‘perfect pairing approximation’. In molecular orbital theory it is known as the bond orbital approximation, which we discussed on p. 123 in the context of Si.
Cooling Of Large Accelerator Magnet Systems
Authors: Asner Fred M 
Published: November 2023

Abstract
Heat losses and heat in leaks in superconducting magnet systems are due to:resistive losses at varying magnetic fields such as magnetization losses and eddy current losses in the non-superconductive cable parts, in structural parts, current feedthrough, cable splices, end connections, etc. beam losses caused by synchrotron radiation, imaging currents in the beam pipes, continuous losses in the circulating beams, and the relative inefficiency of collimators. In highly irradiated beam regions additional heat is deposited in the mag net cold masses due to absorption of secondary particles. heat in leaks caused by thermal conductivity and radiation losses of magnet parts at ambient and different cryogenic temperatures.
Path Integral Representation
Authors: Kashiwa T , Ohnuki Y , Suzuki M 
Published: November 2023

Abstract
In this chapter path integral formulae in various representations will be derived by starting from the Schrodinger equation. In order to obtain a c-number expression for the time evolution operator given in terms of the momentum and the coordinate, first we need to deal with the issue of operator ordering. Then a discussion on the Euclidean technique, with which path integration can prove its real worth, that is where path integration can be regarded as a powerful tool for acquiring quantum information, will be presented. Further, alternative path integral expressions other than those obtained by using the eigen states of the momentum and the coordinate will be presented by utilizing the coherent states. Path integral formulae for the Fermi system will be finally presented, together with guidance on Grass man numbers, the indispensable rudiments for doing this.
Quantum Monte Carlo Method
Authors: Kashiwa T , Ohnuki Y , Suzuki M 
Published: November 2023

Abstract
The path integral discussed in the preceding chapters can be exactly calculated only in a few restricted systems such as harmonic oscillators. The WKB method and perturbational expansions based on the above path integral method are in fact applicable to systems close to classical ones and weakly interacting systems, respectively. However, in order to study interesting phenomena such as high Tc superconductivity, we have to treat strongly correlated systems in which the quantum effect plays an important role. It is effective in these systems to extract some physically crucial contributions numerically. This will be possible if we use the quantum Monte Carlo method. Although there are many different types of quantum Monte Carlo methods, we explain here mainly the quantum statistical Monte Carlo method based on a Trotter-like formula and on the important sampling method applied to transformed classical systems.
Induced Magnetic Anisotropy
Authors: Chikazumi Sōshin , Graham, Jr C D 
Published: November 2023

Abstract
The induced magnetic anisotropy differs from the ordinary magnetic anisotropy discussed in Chapter 12, in that the induced anisotropy is produced by a treatment (often an annealing treatment) that has directional characteristics. Not only the magnitude but also the easy axis of the anisotropy can be altered by appropriate treatments. We shall discuss various types of induced anisotropy in this section.
X-RAY And Gamma-Ray Standards For Detector Calibration
Authors: Lorenz A , Nichols A .L 
Published: November 2023

Abstract
The recommended half-life and X- and gamma-ray emission probability data presented here were prepared by members of a Coordinated Research Programme (CRP) on X-ray and Gamma-ray Standards for Detector Calibration under the auspices of the International Atomic Energy Agency (IAEA). This concerted measurement and evaluation effort has resulted in a significant improvement in the accuracy and consistency of the decay parameters required for the efficiency calibration of X- and gamma-ray detectors.
Tunnelling phenomena
Authors: Kelly M J 
Published: November 2023

Abstract
This is the first of three chapters devoted to the new physics that has been made accessible with the advent of semiconductor multilayers. We shall be concerned with the quantum-mechanical phenomenon that an electron of total energy less than that of a thin potential barrier might not be reflected, as would always happen classically, but rather might pass through the barrier with an exponentially small but finite probability. Tunnelling has been an exploitable phenomenon in solid state physics for some time, and Josephson junction technology makes intimate use of superconducting tunnel junctions. In a wider sense, many of the leakage currents that plague high-performance devices have, in fact, come from carriers tunnelling through barriers that are undesirably thin. We are now able to control the tunnel barrier thickness precisely and to engineer the current-voltage characteristics. The subject has received an added boost through the discovery of resonant tunnelling involving two potential barriers: for certain. well-defined energies the tunnelling probability is not exponentially small, but approaches unity. Application of a suitable bias to a double-barrier structure can establish the condition of resonant tunnelling with a high current density. A further increase in bias takes the structure off resonance, and the current falls. This gives rise to a new form of negative differential resistance with attractive attributes that we shall describe below. Although it has taken some time, the device spin-offs are now becoming apparent. In the mean time, many physicists have explored nearly every conceivable aspect of resonant tunnelling.
Quantum wells and their optical properties
Authors: Kelly M J 
Published: November 2023

Abstract
It is arguable that the most widespread and successful applications of semiconductor multilayers to date exploit the optical properties of quantum wells, i.e. thin layers of a narrow-gap semiconductor sandwiched between layers of wider-gap material. This chapter contains a discussion of much of the relevant physics, with the device applications being described in more detail in Chapters 18 and 19. This chapter also completes the trio of chapters on novel physics in multilayers.
Devices I: field-effect and heterojunction bipolar transistors
Authors: Kelly M J 
Published: November 2023

Abstract
Having established the physics and the technology of semiconductor multilayers, in the following four chapters we consider the way in which that physics is being exploited in commercial and advanced research devices. These chapters are not intended to be complete expositions of the devices, which can be found in standard texts (e.g. Sze 1981, 1990). In this chapter we concentrate on transistors used as switches in digital circuits and as amplifiers in analogue circuits. In the next chapter, we focus on two-terminal devices used as sources, detectors, and mixers of microwaves and millimetre waves. These two chapters cover electronic devices with applications in computation and communications (including radar). In Chapter 18, we concentrate on a range of sources, modulators, and detectors of coherent and incoherent optical signals which find their principal application in optical fibre communication links. In Chapter 19 we describe a wider range of optical devices, used as mid- and far-infrared detectors of radiation and in solar cells.
Devices Ill: lasers, modulators, and detectors
Authors: Kelly M J 
Published: November 2023

Abstract
In this chapter we discuss the components required to generate, control, and detect optical signals at wavelengths of order 0.8-1.5 µm. The growth of communication systems based on optical fibre as the transmission medium has been spectacular over the last two decades. In 1993 alone, 80 000 route kilometres of undersea cable was programmed for installation. The bandwidth is enormous when the carrier frequency is of order 300 THz, compared with the c.100 GHz in the last chapter, although one trades off propagation in free space there for that within a fixed link here. The optimum wavelengths for transmission in silica fibres are 1.3 µm and 1.55 µm corresponding respectively to a wavelength where two non-linear effects cancel each other and to a minimum in the absorption, both of which permit long-haul communications without significant distortion or weakenipg of the optical signals {Tsang 1985). This has led to the development of high-performance lasers at both wavelengths. With the discovery that erbium-doped fibres can act as lasers operating at 1.5 µm while pumped at 0.98 µm (Barnes et al. 1989), methods are being sought of pumping fibres with semiconductor lasers at a comparable wavelength. In the first part of this chapter, we describe the subsequent generations of lasers with reference to the GaAs-AIGaAs system (bulk GaAs lases at a wavelength of 0.86 µm determined by the bandgap), and then we apply some of the principles behind these lasers to those operating at longer wavelengths. The storage and reading of data by optical means is another major area of application. At present GaAs-based lasers (costing less than £0.1 each!) are used. The optical systems for writing and reading digital information are limited by diffraction effects, and so ever-shorter wavelengths are required for increased data storage density. GaAllnP-based red lasers are available. Most recently the effort to produce semiconductor laser diodes that operate in the visible has paid off with initial reports of (low-temperature) lasers in the blue and green (Haase et al. 1991, Jeon et al. 1992).
Devices IV: infrared and solar devices
Authors: Kelly M J 
Published: November 2023

Abstract
In the last of these chapters devoted to the applications of multilayer semiconductor structures, we concentrate on two further optical devices, namely infrared detectors and solar cells. The former exploit inter-sub-band absorption in quantum wells, introduced briefly in chapter 10, Section 10.2.6, while the latter use multilayers to increase the absorption from the solar spectrum. Both devices have specialized applications, where the cost of high performance is justified. Thermal imaging and night vision, based on infrared radiation in the 8—14 μm atmospheric window not affected by water vapour, is becoming increasingly exploited outside the military arena for which it was developed, for example in see-through-smoke applications associated with fire fighting, thermal imaging of people buried in collapsed buildings, surveillance and security, etc. The applications have in the past withstood the expense of less stable and convenient materials such as HgCdTe alloys, exploiting a principal bandgap of c.10 pm for an 18 per cent CdTe-82 per cent HgTe alloy (cf. Chapter 1, Fig. 1.8). The prospect of replacing this material with the rather more mature GaAs-AlGaAs system is very attractive, and the pace of development has been particularly rapid in recent years (Levine 1993). In contrast, solar cells for domestic and commercial applications must be cheap before being highly efficient. In space and in other applications where access is difficult (e.g. weather or other monitoring from remote locations, and in some military arenas) one requires a compact, light, and highly efficient method for capturing solar energy and converting it into electricity (Bube 1993).
Radical alternatives
Authors: Kelly M J 
Published: November 2023

Abstract
So far in this text we have dealt with multilayers of conventional III-V and group IV semiconductors, and described what has been the mainstream research in semiconductor science and technology. The rapid advances within this technology have spurred those working in other fields and with other materials to try to match and surpass these achievements. In this closing chapter we introduce some of these radical alternatives to mainstream semiconductor science and technology. While some scientists strive in the vain hope of outperforming Si at what Si is best at, the main advances are likely to be in those areas where the final devices perform functions not available with Si or III-V semiconductors. As mentioned in the early chapters, III-V materials have specific properties, not available in Si, that have allowed them flourish, namely (i) the direct nature of the bandgap, making optical functions efficient, (ii) the turnover in the velocity-field characteristic leading to negative differential resistance and microwave sources, and (iii) the ability of substrates to retain a semi-insulating property after being taken through device processing. Increases in device speed by a factor of 3 in III-V materials compared with Si allow windows of opportunity for III-V digital applications, but in the end Si technology wins out through the greater maturity of its technology. Radical alternative technologies will need distinctive attributes not available with the group IV and III-V materials and devices.
Polymer-polymer interactions in dilute solution
Authors: Selser Jim 
Published: November 2023

Abstract
This chapter deals with interactions between polymers in dilute solution. The chapter does not present a summary either of the results of an extensive search of the relevant literature to date or of a consideration of the behaviours of all possible kinds of polymers under all possible circumstances. Instead, it deals primarily with light scattering studies of interactions in binary systems between non-electrolytic polymer coils, carried out by the author and his coworkers. Two themes emphasized throughout this chapter are: (1) the benefits of using static light scattering (‘SLS’) and the dynamic light scattering technique of photon correlation spectroscopy (‘ DLS’) together to investigate polymer-polymer interactions in dilute solution (see Chapter 8 of ref. 6 and Chapter 13 of this volume), and (2) the interplay between intra-polymer and inter-polymer behaviour in dilute solution.
Scattering from block copolymer micellar systems
Authors: Tuzar Zdeněk , Kratochvil Pavel 
Published: November 2023

Abstract
Block and graft copolymers in solution in selective solvents, that are good for one block and poor for the other, self-associate forming multimolecular micelles, the cores of which consist of insoluble blocks, while the soluble blocks are located in protective shells. A typical association number (i.e. the number of copolymer molecules in a micelle) is from tens to hundreds. These micelles, with a narrow molar mass and size distribution, are in dynamic equilibrium with molecularly dissolved copolymer molecules (unimers). Unlike aqueous micellar systems of soaps and surfactants, block copolymer micellar systems in both organic and aqueous selective solvents have very low, usually imperceptible, critical micelle concentrations (CMC).
Classical radiation physics
Authors: Akhmanov S A , Nikitin S YU 
Published: November 2023

Abstract
Hertz’s experiment. The atom as an elementary source of light. The classical model of the atom. Emission from a charge and Emission conditions. Calculation of the vortical component of the field. A rigorous solution of the problem of dipole emission. Harmonic oscillations of a dipole. The total power of dipole radiation. The decay of dipole oscillations due to emission of radiation.