bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of thermal misbalance on magnetohydrodynamic modes in coronal magnetic cylinders
Authors: Hejazi S. M. , Van Doorsselaere T. , Sadeghi M. , Kolotkov D. Y. , Hermans J. 
Published: January 2025

Aims. It is well demonstrated that thermal misbalance, arising from the discrepancy between optically thin radiative energy loss and heating energy gain, disrupts the adiabatic nature of solar corona plasmas, directly affecting the propagation of slow magnetoacoustic waves. However, the extent to which this thermal misbalance, acting as a dispersion factor of an arbitrary intensity, influences the use of slow modes as seismological tools and affects sausage and kink harmonic modes within a magnetic plasma flux tube, remains unresolved.
Methods. This study investigates the dispersion of magnetohydrodynamic waves influenced by thermal misbalance in a cylindrical configuration with a finite axial magnetic field within solar coronal plasmas. Specifically, it examines how thermal misbalance, characterized by two distinct timescales directly linked to the cooling and heating functions, influences the dispersion relation. This investigation is a key approach for understanding non-adiabatic effects on the behaviour of these waves.
Results. The analysis explores the impact of non-adiabatic effects due to classical thermal misbalance, where the heating and cooling timescales vary across a range of values corresponding to each magnetohydrodynamic mode. The dispersion relation for magnetohydrodynamic waves propagating through a magnetic plasma tube, aligned with a finite magnetic field, is calculated under coronal conditions in the linear regime.
Conclusions. Our findings reveal that the effect of thermal misbalance on fast sausage and kink modes, consistent with previous studies on slabs, is small but slightly more pronounced than previously thought. The impact is smaller at long-wavelength limits but increases at shorter wavelengths, leading to higher damping rates. This minor effect on fast modes occurs despite the complex interaction of thermal misbalance terms within the dispersion relation, even at low-frequency limits defined by the characteristic timescales. Additionally, a very small amplification is observed, indicating a suppressed damping state for the long-wavelength fundamental fast kink mode. In contrast, slow magnetoacoustic modes are significantly affected by thermal misbalance, with the cusp frequency shifting slightly to lower values, which is significant for smaller longitudinal wavenumbers. This thermal misbalance likely accounts for the substantial attenuation observed in the propagation of slow magnetoacoustic waves within the solar atmosphere. The long-wavelength limit leads to an analytical expression that accurately describes the frequency shifts in slow modes due to misbalance, closely aligning with both numerical and observational results.
Rydberg blockade and quantum squeezing effects in a microwave mediated five-level inverted Y-type atomic system
Authors: Laskar Rejjak , Hossain Md Mabud , Saha Jayanta K 
Published: January 2025

Abstract
We propose a quantum mechanical model for observing Rydberg blockade and squeezing effects using a microwave field-assisted five-level inverted Y-type atom-laser interaction system. Using the mean field approximation, we calculate the mean and squeezed values of collective atomic operators and the probe field’s annihilation operator. Our model predicts that the presence of a signal field increases the number of probe photons transmitted under Rydberg blockade conditions as the control field strength increases. Additionally, it shows that higher number of probe photons are transmitted in the linear interaction regime compared to the non-linear regime. Under Rydberg blockade conditions, the probability of two or more photons in the same Rydberg superatom can be tuned by switching between linear and non-linear interaction regimes, and the positions of bunching or anti-bunching can be adjusted by toggling the signal field on or off. In the presence of the signal field, squeezing in probe transmittance can be maximized in both linear and non-linear regimes by increasing the strength of the control field.
Determination of QED correction to the 413 nm tune-out wavelength of 4He(

2
3

S
1

) using the radiative potential method
Authors: Lu Shan-Shan , Zhang Yong-Hui , Shi Ting-Yun , Tang Li-Yan 
Published: January 2025

Abstract
In contrast to previous perturbation calculations that employed the nonrelativistic quantum electrodynamics (QED) method, we have developed the relativistic configuration interaction combined with radiative potential (RCIRP) method to determine the QED correction of 413 nm tune-out wavelength of metastable helium, where the radiative potential operator is directly incorporated into the Dirac–Coulomb–Breit Hamiltonian to account for QED contributions. When the laser polarization vector is parallel or perpendicular to the quantization axis, present results for each magnetic sublevel of

2

3

S
1

state are in good accordance with existing theoretical and experimental values, indicating the correctness and effectiveness of the RCIRP method in the determination of QED corrections. Additionally, we find that the static dipole polarizability and tune-out wavelength exhibit high sensitivity to QED effect when the laser polarization vector is parallel to the quantization axis and the magnetic sublevel

M
J

=
±
1

, which provides theoretical support for future experimental measurement to test QED calculations.
Analytical solutions for optimal photon absorption into inhomogeneous spin memories
Authors: Bernád József Zsolt , Schilling Michael , Wen Yutian , Müller Matthias M , Calarco Tommaso , Bertet Patrice , Motzoi Felix 
Published: January 2025

Abstract
We investigate for optimal photon absorption a quantum electrodynamical model of an inhomogeneously-broadened spin ensemble coupled to a single-mode cavity. Solutions to this problem under experimental assumptions are developed in the Schrödinger picture without using perturbation theory concerning the cavity-spin interactions. Furthermore, we exploit the possibility of modulating the frequency and coupling rate of the resonator. We consider a one-photon input pulse and show some optimal scenarios, where exact formulas and numerical results are obtained for the absorption probabilities and the optimal pulse shapes. In particular, if the external loss dominates the internal loss of the cavity, we find the optimal cooperativity for different parameters and identify cases where absorption with a success probability larger than 99% is achieved.
Factors associated with radiation risk perception among Japanese university students
Authors: Yamaguchi Takumi , Yanagida Nobuhiko , Yamamoto Naoyuki , Matsunari Yuko 
Published: January 2025

Abstract
After the Fukushima Daiichi Nuclear Power Station accident, various information about radiation circulated throughout Japan, leading to diverse perceptions regarding the situation in Fukushima. These perceptions contributed to the social challenges faced by the residents of Fukushima at the time, including prejudice and discrimination. This heightened concern about radiation exposure, particularly among younger generations who were considering marriage or starting families. In the present study, we aimed to investigate the present status of radiation risk perception among university students in Japan and the factors associated with radiation risk perception among these students. A questionnaire survey was administered to university students throughout Japan. We collected demographic information as well as queried their perception of radiation risk (delayed health effects and genetic effects). The results showed that approximately 60% and 40% of respondents believed that delayed effects and genetic effects would occur among residents of Fukushima, respectively. Additionally, having a university major other than studying radiation techniques and living in western Japan were associated with these perceptions of risk. In the future, enhancing risk communication, especially among young populations in western Japan, is necessary to dispel anxiety about the risks from radiation exposure.
Study of the TOFPET2c ASIC in time-of-flight detection of x-rays for scatter rejection in medical imaging applications
Authors: Gaulin L-D , Nadig V , Herweg K , Lemaire G , Gagnon F , Bouchard J , Rossignol J , Schulz V , Fontaine R , Gundacker S 
Published: January 2025

Abstract

Objective. Integrating time-of-flight (ToF) measurements in radiography and computed tomography (CT) enables an approach for scatter rejection in imaging systems that eliminates the need for anti-scatter grids, potentially increasing system sensitivity and image quality. However, present hardware dedicated to the time-correlated measurement of x-rays is limited to a single pixel physically too large for the desired spatial resolution. A switch to highly integrated electronics and detectors is needed to progress towards detector arrays capable of acquiring images, while offering a timing resolution below 300 ps FWHM to achieve scatter rejection comparable to current anti-scatter grids. Approach. Using off-the-shelf scintillators, photodetectors and readouts designed for ToF positron emission tomography (PET) provides a preliminary evaluation of available highly integrated readout systems supporting detector arrays for ToF scatter rejection. The TOFPET2c ASIC from PETSys offers an established development platform necessary for fast and reliable results, with no known limitation regarding time-correlated detection of medical imaging x-rays (20–140 keV). Main results. Reliable photon detection down to 31 keV was achieved, reaching energy resolutions from 23% to 92% FWHM throughout the desired energy range. Optimal detector timing resolution (DTR) from 250 ps FWHM at 130 keV to 678 ps FWHM at 30 keV was reached. Strong time walk effects were observed, showing a time shift of 642 ps up to 1740 ps between events spanning the energies used in x-ray medical imaging. Significance. The TOFPET2c ASIC has shown its potential for ToF scatter rejection, but meets the time resolution requirement of 300 ps FWHM only for limited energies (110–140 keV). This significant timing degradation observed at lower energies limits the use of the TOFPET2c ASIC for ToF scatter rejection, but offers significant advancements regarding the understanding of the phenomenon arising from the time-correlated detection of medical imaging x-rays.
Resilience–runtime tradeoff relations for quantum algorithms
Authors: Pedro García-Pintos Luis , O’Leary Tom , Biswas Tanmoy , Bringewatt Jacob , Cincio Lukasz , Brady Lucas T , Liu Yi-Kai 
Published: January 2025

Abstract
A leading approach to algorithm design aims to minimize the number of operations in an algorithm’s compilation. One intuitively expects that reducing the number of operations may decrease the chance of errors. This paradigm is particularly prevalent in quantum computing, where gates are hard to implement and noise rapidly decreases a quantum computer’s potential to outperform classical computers. Here, we find that minimizing the number of operations in a quantum algorithm can be counterproductive, leading to a noise sensitivity that induces errors when running the algorithm in non-ideal conditions. To show this, we develop a framework to characterize the resilience of an algorithm to perturbative noises (including coherent errors, dephasing, and depolarizing noise). Some compilations of an algorithm can be resilient against certain noise sources while being unstable against other noises. We condense these results into a tradeoff relation between an algorithm’s number of operations and its noise resilience. We also show how this framework can be leveraged to identify compilations of an algorithm that are better suited to withstand certain noises.
Floquet topological phase transitions in 2D Su–Schrieffer–Heeger model: interplay between time reversal symmetry breaking and dimerization
Authors: Pena Adrian , Ostahie Bogdan , Radu Cristian 
Published: January 2025

Abstract
We theoretically study the 2D Su-Schrieffer-Heeger model in the context of Floquet topological insulators (FTIs). FTIs are systems which undergo topological phase transitions, governed by Chern numbers, as a result of time reversal symmetry (TRS) breaking by a time periodic process. In our proposed model, the condition of TRS breaking is achieved by circularly polarized light irradiation. We analytically show that TRS breaking is forbidden in the absence of second order neighbors hopping. In the absence of light irradiation, we identify a symmetry-protected degeneracy and prove the appearance of a flat band along a specific direction in the momentum space. Furthermore, we employ a novel method to show that the four unit cell atoms, in the absence of irradiation, can be interpreted as conserved spin states. With the breaking of TRS via light irradiation, these spin states are no longer conserved, leading to the emergence of chiral edge states. We also show how the interplay between the TRS breaking and dimerization leads to some complex topological phase transitions. The validity of our findings is substantiated through Chern numbers, spectral properties, localization of chiral edge states and simulations of quantum Hall transport. Our model is suitable not only for condensed matter (materials), but also for cold gases trapped in optical lattices or topolectrical circuits.
Recent progress on stability and applications of flexible perovskite photodetectors
Authors: Hu Ying , Zhang Qianpeng , Han Junchao , Lian Xinxin , Lv Hualiang , Pei Yu , Shen Siqing , Liang Yongli , Hu Hao , Chen Meng , Mo Xiaoliang , Chu Junhao 
Published: January 2025

Abstract
Flexible photodetectors have garnered significant attention by virtue of their potential applications in environmental monitoring, wearable healthcare, imaging sensing, and portable optical communications. Perovskites stand out as particularly promising materials for photodetectors, offering exceptional optoelectronic properties, tunable band gaps, low-temperature solution processing, and notable mechanical flexibility. In this review, we explore the latest progress in flexible perovskite photodetectors, emphasizing the strategies developed for photoactive materials and device structures to enhance optoelectronic performance and stability. Additionally, we discuss typical applications of these devices and offer insights into future directions and potential applications.
Calibrating laser Doppler anemometers utilizing an optical chopper
Authors: Crowley Christopher J , Shinder Iosif I , Moldover Michael R , Boyd Joey T , Filla B James , Johnson Aaron N 
Published: January 2025

Abstract
Laser Doppler anemometers (LDAs) use scattered light to determine velocity components of a flowing fluid. The operating principal of LDAs is simple conceptually; however, it is impractical to trace the LDA-determined velocities to the SI by characterizing the LDA’s subsystems that generate, detect, and process optical signals because these subsystems are complex and include proprietary features. To circumvent this, we calibrated the complete LDA systems utilizing an optical chopper blade as an accurate, SI-traceable velocity standard. The calibrations achieved the expanded velocity uncertainty 0.094% at a 95% confidence level. We calibrated two LDAs that differed in manufacturer, focal length (in the ratio 3.3:1), sensing volume (in the ratio 100:1), and orientation (vertical and horizontal bisectors of the LDA’s crossing beams). To compare the calibrations, we measured airspeeds in NIST’s wind tunnel using both LDAs. The results differed from each other by, at most, 0.2% throughout the airspeed range (0.5–30) m s−1.
A bilateral comparison of 227Th activity standards between National Physical Laboratory and National Institute of Standards and Technology
Authors: Fenwick Andrew J , Bergeron Denis E , Bendall Emma , Broder Brittany A , Cessna Jeffrey T , Collins Seán M , Pibida Leticia , Ramirez Natasha , Napoli Elisa 
Published: January 2025

Abstract
The National Physical Laboratory (United Kingdom) and the National Institute of Standards and Technology (United States) each determined the massic activity of a common solution of 227Th. Measurements at both laboratories were performed before radioactive equilibrium. The direct comparison showed good accord between the laboratories’ activity standards with a t-test score of 0.15 based on ionization chamber measurements. Challenges associated with pre-equilibrium comparisons are addressed and multiple comparison approaches are presented. The use of a hybrid comparison methodology using a model to correct asynchronously acquired data to an intermediate timepoint mitigates major sources of uncertainty and potential bias in extreme cases.
Transport and profile broadening in the private flux region of ASDEX upgrade and role for power exhaust
Authors: Brida D. , Grenfell G. , Grover O. , Silvagni D. , Faitsch M. , Stroth U. ,   the ASDEX Upgrade Team,   the EUROfusion Tokamak Exploitation Team
Published: January 2025

Abstract
Understanding the transport processes that determine the plasma profile widths in the scrape-off layer (SOL) and divertor region of tokamaks is crucial for successful power and particle exhaust management in future devices. Plasma transport from the SOL into the private flux region (PFR) broadens the profiles and could mitigate the power exhaust challenge. Analysis of ion current profiles, measured by Langmuir probes in the ASDEX upgrade (AUG) tokamak, shows that the ion current width in the PFR, normalized by the flux expansion between outer target and midplane, is about 1.2 mm in L-mode and 0.9 mm in inter-ELM H-mode plasmas. The measured widths agree within a factor of two with predictions from an analytical model, based on Pfirsch-Schlüter flows. According to the model, the ion PFR width increases with the distance ΔR between the outer target and X-point major radii, and scales inversely with the poloidal magnetic field

B

p

. For the tokamaks ITER and SPARC the model predicts PFR widths below 0.3 mm.
Infernal instabilities in negative-triangularity plasmas with negative central shear
Authors: Zhang X.M. , Li L. , Liu Y.Q. , Dong Z.Y. , Li J.W. , Liang Y. , Zhong F.C. 
Published: January 2025

Abstract
A systematic numerical investigation is carried out to understand magnetohydrodynamic stability of the ideal infernal-kink instability in tokamak plasmas with both negative triangularity (neg-D) shaping and negative central shear for the equilibrium safety factor profile. The latter is motivated by the desire to form the internal transport barrier in the neg-D configuration, which is known to have difficulty in forming the edge transport barrier. The infernal-kink mode is generally found to be more unstable in neg-D plasmas as compared to their positive D-shaped (pos-D) counterpart. This is mainly due to less favorable (or even unfavorable) average magnetic curvature near the radial location of the minimum safety factor (

q

min

) as compared to the pos-D configuration. The larger Shafranov shift associated with the neg-D shape helps the mode stabilization but is not sufficient to overcome the destabilizing effect due to bad curvature. Strong poloidal mode coupling due to plasma shaping (toroidicity, elongation, triangularity, etc.) helps explain the slight shift with respect to that predicted by the analytic theory of the peak location of the computed mode growth versus

q

min

.
Reduced aerosols and intensified summertime rainfall in India during the pandemic suggest potentially more amplified precipitation in the future
Authors: Wang Fan , Gao Meng 
Published: January 2025

Abstract
Aerosol pollution is anticipated to decrease in the future, yet the associated effects of reduced aerosol loading on precipitation remain insufficiently explored. Widespread reductions in anthropogenic emission during COVID-19 lockdowns offer a unique opportunity to understand precipitation responses to changes in anthropogenic aerosols. Based on observations and regional and global climate-chemistry coupled model simulations, we attribute unprecedented precipitation in India during the 2021 lockdown to decreased aerosol levels due to emission reductions. Reduced aerosol loading leads to a northward shift of the subtropical westerly jet, which induces a westward movement of the subtropical southern branch trough and negative sea-level pressure anomalies over the eastern Arabian Sea. This shift facilitates water vapor transport from surrounding oceans to land, increasing precipitation in India by approximately 24.2% in May according to the Weather Research and Forecasting model coupled with chemistry simulations and by 28.5% over the entire lockdown period according to the Community Earth System Model version 2.1.3 simulations. Future projections under the lower aerosol emission scenario indicate an additional enhancement in monsoon precipitation in India. Our findings highlight the complex interplay between aerosol emissions and hydrometeorological dynamics, with implications for understanding future precipitation changes and providing theoretical reference for water resource management.
Arctic sea ice melting has produced distinct sea ice-atmosphere coupled patterns
Authors: Wu Bingyi 
Published: January 2025

Abstract
The possible influence of Arctic sea ice on weather events and climate variations has received considerable attention, while the evolution of its relationship with interannual variations of winter temperature across much of Eurasia remains poorly understood. This study quantitatively describes two distinct coupled patterns between autumn Arctic sea ice concentration in the Barents–Kara seas and the subsequent winter regional temperature over Eurasia. The leading coupled pattern dominantly depicts interannual variations of the cold Arctic―warm Eurasia or warm Arctic—cold Eurasia configuration, differing from the background warming pattern. While the second coupled pattern describes in-phase interannual variations of winter temperature over the Arctic and across much of Eurasia. This second pattern displayed an interdecadal transition in the early 2010s, from frequent occurrences of the cold Arctic―cold Eurasia pattern to the dominant warm Arctic―warm Eurasia configuration. Through this interdecadal transition, the warm Arctic―warm Eurasia configuration replaced the leading coupled pattern. The previously proposed the tropospheric and stratospheric processes cannot fully explain this Arctic―Eurasia temperature configuration. These findings underscore the pivotal role of Arctic sea ice melting in influencing the interannual and interdecadal variations of winter atmospheric circulation patterns and have significant implications for predicting short-term winter temperature trends over Eurasia.