Journal of Low Temperature Physics最新文献_第3页

Effects of Lanthanum Doping on Structural Evolution, Morphological Features, and Flux Pinning in FeSe0.5Te0.5 Single Crystals with Machine Learning Assistance 在机器学习辅助下，镧掺杂对FeSe0.5Te0.5单晶结构演化、形态特征和通量钉钉的影响

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-08-10 DOI: 10.1007/s10909-026-03455-y

Jie Zhang, Jian Peng, Jens Hänisch, Shengnan Zhang, Shunpeng Shi, Chuanyu Zhang, Fanggong Cai, Guo Yan, Yong Zhao

{"title":"Effects of Lanthanum Doping on Structural Evolution, Morphological Features, and Flux Pinning in FeSe0.5Te0.5 Single Crystals with Machine Learning Assistance","authors":"Jie Zhang, Jian Peng, Jens Hänisch, Shengnan Zhang, Shunpeng Shi, Chuanyu Zhang, Fanggong Cai, Guo Yan, Yong Zhao","doi":"10.1007/s10909-026-03455-y","DOIUrl":"10.1007/s10909-026-03455-y","url":null,"abstract":"<div>Single crystals of LaxFe1−xSe0.5Te0.5 (x = 0, 0.02, 0.04, 0.06, 0.08) were grown using the self-flux method. A systematic investigation of the effects of La addition revealed changes in the lattice parameters, with the lattice parameter a decreasing and the lattice parameter c showing a slight increasing tendency. The superconducting transition temperature showed no significant dependence on La doping. However, when x reached 0.04, the critical current density derived from magnetization loops using the Bean model increased. The dominant pinning mechanism induced by La in FeSe0.5Te0.5 was identified as normal point pinning at low magnetic fields. At the same time, machine learning was employed to quantitatively model the composition–property relationship between La doping and superconducting and magnetic properties; the results indicate that this method is effective in capturing experimental trends. This work demonstrates that rare earth doping could be a viable strategy for optimizing flux pinning in iron-based superconductors.</div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03455-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design and Room-Temperature ESR Characterization of a Compact Planar Loop-Gap Resonator near 12 GHz for Prospective Cryogenic Applications 面向低温应用的12 GHz紧凑平面环隙谐振器的设计和室温ESR表征

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-08-08 DOI: 10.1007/s10909-026-03457-w

Yuya Ishikawa, Yutaka Kurachi, Jarno Järvinen, Sergey Vasiliev, Yutaka Fujii

{"title":"Design and Room-Temperature ESR Characterization of a Compact Planar Loop-Gap Resonator near 12 GHz for Prospective Cryogenic Applications","authors":"Yuya Ishikawa, Yutaka Kurachi, Jarno Järvinen, Sergey Vasiliev, Yutaka Fujii","doi":"10.1007/s10909-026-03457-w","DOIUrl":"10.1007/s10909-026-03457-w","url":null,"abstract":"<div>We report the design, fabrication, microwave characterization, and room-temperature ESR demonstration of a compact planar loop-gap resonator operating near 12 GHz. The resonator was fabricated by etching a 20-µm-thick copper layer on a glass-composite substrate and consisted of a 4.2-mm-diameter circular conductor with a 0.15-mm gap. Non-contact coupling to a stripline was characterized by varying the relative lateral and vertical positions of the resonator. At the position giving the largest resonance dip, the resonance frequency and loaded Q-factor were 12.2 GHz and 67.8, respectively, corresponding to a bandwidth of approximately 180 MHz. A first-order lumped RLC description was used to interpret the measured resonance characteristics. Room-temperature continuous-wave ESR measurements of DPPH demonstrated spin detection near 12.7 GHz with a signal-to-noise ratio of approximately 20. The present results demonstrate a simple planar fabrication and coupling approach for compact ESR resonators.</div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03457-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148751154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Distinguishing Features of Longitudinal Magnetoconductivity for a Rarita–Schwinger–Weyl Node rariita - schwinger - weyl节点纵向导电性的区别特征

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-08-07 DOI: 10.1007/s10909-026-03452-1

Ipsita Mandal

引用次数: 0

Zero-Point Energy of a Trapped Ultracold Fermi Gas at Unitarity: Squeezing the Heisenberg Uncertainty Principle and Suppressing the Pauli Principle to Produce a Superfluid State 在统一处捕获的超冷费米气体的零点能量：压缩海森堡测不准原理和抑制泡利原理以产生超流体状态

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-08-06 DOI: 10.1007/s10909-026-03456-x

D. K. Watson

{"title":"Zero-Point Energy of a Trapped Ultracold Fermi Gas at Unitarity: Squeezing the Heisenberg Uncertainty Principle and Suppressing the Pauli Principle to Produce a Superfluid State","authors":"D. K. Watson","doi":"10.1007/s10909-026-03456-x","DOIUrl":"10.1007/s10909-026-03456-x","url":null,"abstract":"<div>The zero-point energy of a trapped ultracold Fermi gas at unitarity is investigated in relation to the combined effects of the Heisenberg uncertainty principle and the Pauli principle. This lowest allowed quantum state is a superfluid state which has been studied extensively both experimentally and theoretically. The method used for the current investigation is based on a recent series of papers that proposed microscopic dynamics based on normal modes to describe superfluidity instead of real-space Cooper pairs. This approach yielded excellent agreement with experimental data for multiple properties and allowed the microscopic behavior underlying these results as well as the basis of universal behavior to be analyzed in detail using the group theoretic basis of this general N-body approach. This microscopic picture is now used to elucidate the roles played by the uncertainty principle and the Pauli principle in determining the energy and character of the lowest allowed quantum state. The squeezing of the Heisenberg uncertainty principle, a well-known phenomenon in other systems, is proposed to play a role in the creation of superfluidity. The suppression of the Pauli principle is introduced as a new phenomenon.</div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148750771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Crossover From Classical to Quantum Transport in a Weakly-Interacting Fermi Gas 弱相互作用费米气体中从经典到量子输运的交叉

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-08-04 DOI: 10.1007/s10909-026-03430-7

Hadrien Kurkjian

引用次数: 0

Effectiveness of Some 0 dB Cryogenic Microwave Attenuators as Thermal Heatsinks 一些0 dB低温微波衰减器作为散热器的有效性

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-08-03 DOI: 10.1007/s10909-026-03453-0

J. T. Klomp, Haoyun Huang, G. A. Csáthy

引用次数: 0

AC Magnetic Susceptibility in the Antiferromagnetic Transition of (alpha ) (mathrm{text {-}Dy}_2) (textrm{S}_3) and the Weak-Ferromagnetic Transition of (alpha ) (mathrm{text {-}Sm}_2) (textrm{S}_3) 的反铁磁跃迁和弱铁磁跃迁中的交流磁化率(alpha )(mathrm{text {-}Dy}_2)(textrm{S}_3)(alpha ) (mathrm{text {-}Sm}_2) (textrm{S}_3)

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-07-31 DOI: 10.1007/s10909-026-03449-w

Shuji Ebisu, Takeru Kona, Ryuta Horii, Daichi Yamakawa, Ryo Ishigaki, Masanori Miyazaki

{"title":"AC Magnetic Susceptibility in the Antiferromagnetic Transition of (alpha ) (mathrm{text {-}Dy}_2) (textrm{S}_3) and the Weak-Ferromagnetic Transition of (alpha ) (mathrm{text {-}Sm}_2) (textrm{S}_3)","authors":"Shuji Ebisu, Takeru Kona, Ryuta Horii, Daichi Yamakawa, Ryo Ishigaki, Masanori Miyazaki","doi":"10.1007/s10909-026-03449-w","DOIUrl":"10.1007/s10909-026-03449-w","url":null,"abstract":"<div>Rare earth sesquisulfides ({alpha })-({R_2})S(_3) (R = Dy, Sm) possess an orthorhombic crystal structure having two crystallographically inequivalent rare earth sites, R1 and R2. The compound (alpha )-(textrm{Dy}_2textrm{S}_3) exhibits successive antiferromagnetic transitions at (T_text {N1} = 11.4) K and (T_text {N2} = 6.4) K, while ({alpha })-Sm(_2)S(_3) shows successive weak-ferromagnetic transitions at (T_text {C1} = 3.6) K and (T_text {C2} = 1.8) K. Furthermore, they are fascinating because they exhibit a very large increase and recovery in electrical resistivity within a narrow temperature range just above (T_text {N2}) and (T_text {C1}), respectively. In this study, the AC magnetic susceptibility was measured near (T_text {N1}) and (T_text {N2}) using ({alpha })-Dy(_2)S(_3) single crystals, and near (T_text {C1}) using ({alpha })-Sm(_2)S(_3) single crystals. The imaginary part of AC susceptibility for each compound exhibited sharp peak near (T_text {N2}) or (T_text {C1}), respectively, clearly indicating a phase delay in the magnetic moment motion within each temperature range, where it could not follow the changes in the AC magnetic field. Furthermore, it was found that in ({alpha })-Dy(_2)S(_3), the peak height increases with increasing AC magnetic field frequency, whereas in ({alpha })-Sm(_2)S(_3), it decreases, reflecting the difference in magnetic ordering between the two compounds.</div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148628526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Linear Magnetic Field Suppression of the Superconducting Gap in NbTi and MgB(_2) Wires 线性磁场对NbTi和MgB (_2)导线超导间隙的抑制

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-07-31 DOI: 10.1007/s10909-026-03444-1

Jaime Rumeu Ozores, Óscar Bou Marqués, Jose Antonio Moreno, Daniel Gajda, Michał Babij, Lan Maria Tran, Andrzej Zaleski, Edwin Herrera, Isabel Guillamón, Hermann Suderow

{"title":"Linear Magnetic Field Suppression of the Superconducting Gap in NbTi and MgB(_2) Wires","authors":"Jaime Rumeu Ozores, Óscar Bou Marqués, Jose Antonio Moreno, Daniel Gajda, Michał Babij, Lan Maria Tran, Andrzej Zaleski, Edwin Herrera, Isabel Guillamón, Hermann Suderow","doi":"10.1007/s10909-026-03444-1","DOIUrl":"10.1007/s10909-026-03444-1","url":null,"abstract":"<div>Superconducting vortices have a normal core and are pinned at imperfections, facilitating large current flow. Applications such as high-field solenoids or superconducting motors rarely use pure materials, as these are brittle, and instead employ superconductors embedded in ductile matrices (e.g., Cu or Ag). Processing superconductors into grains and then embedding in wires can significantly affect their properties, which remain less explored than in pure materials. In particular, the superconducting gap, relevant for vortex pinning, has been little studied in wires. Here, we determine the gap as a function of temperature and magnetic field in NbTi and MgB(_2) wires using scanning tunneling microscopy. We find strong gap inhomogeneity, with (Delta _{NbTi}=0.9pm 0.6) mV and (Delta _{MgB_2}=1.8pm 0.2) mV. The temperature dependence follows BCS theory. Under magnetic field, the gap decreases approximately linearly, deviating from the usual (left( 1-frac{H}{H_{c2}}right) ^2) behavior. We attribute this deviation to gap inhomogeneity arising possibly due to processing the materials into a wire. Our work shows that gap structure studies could complement efforts to improve superconducting properties of wires.\u0000</div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03444-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148628527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spin-Dependent Quantum Interference and Persistent Spin Currents in Tunnel-Coupled Double Quantum Rings with Rashba Spin–Orbit Interaction 具有Rashba自旋-轨道相互作用的隧道耦合双量子环中自旋依赖的量子干涉和持续自旋电流

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-07-30 DOI: 10.1007/s10909-026-03454-z

B. G. Ibragimov, G. B. Ibragimov, S. A. Zalova

{"title":"Spin-Dependent Quantum Interference and Persistent Spin Currents in Tunnel-Coupled Double Quantum Rings with Rashba Spin–Orbit Interaction","authors":"B. G. Ibragimov, G. B. Ibragimov, S. A. Zalova","doi":"10.1007/s10909-026-03454-z","DOIUrl":"10.1007/s10909-026-03454-z","url":null,"abstract":"<div>We present a theoretical study of spin-dependent quantum interference and persistent spin currents in tunnel-coupled double quantum rings in the presence of Rashba spin–orbit interaction and an external magnetic field. Within the effective-mass framework, the electronic spectrum is obtained by numerical diagonalization, and the influence of magnetic flux and spin–orbit coupling on the energy levels is analyzed. The results indicate that the energy spectrum exhibits oscillatory behavior as a function of magnetic flux, characteristic of the Aharonov–Bohm effect. Tunnel coupling leads to the formation of bonding and antibonding states, while Rashba spin–orbit interaction introduces spin-dependent modifications, including level splitting and anticrossings. The ground state energy shows periodic dependence on the magnetic flux, reflecting quantum interference effects. Furthermore, a finite equilibrium persistent spin current is obtained, whose behavior is influenced by both tunnel coupling and spin–orbit interaction. The interplay between these effects suggests that the system parameters can be tuned by external fields. These findings contribute to the understanding of spin-dependent quantum transport in mesoscopic ring structures and may be relevant for future studies of spin-related phenomena. </div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Measurement of Phonon Angular Momentum via the Einstein-de Haas Effect, Fiber-Optic Interferometry, and a Single-Crystal Silicon Torsional Oscillator 利用爱因斯坦-德-哈斯效应、光纤干涉测量和单晶硅扭转振荡器测量声子角动量

IF 1.2 3区物理与天体物理

Journal of Low Temperature Physics Pub Date : 2026-07-29 DOI: 10.1007/s10909-026-03447-y

Matt Dwyer, Devan Shoemaker, John T. Markert

{"title":"Measurement of Phonon Angular Momentum via the Einstein-de Haas Effect, Fiber-Optic Interferometry, and a Single-Crystal Silicon Torsional Oscillator","authors":"Matt Dwyer, Devan Shoemaker, John T. Markert","doi":"10.1007/s10909-026-03447-y","DOIUrl":"10.1007/s10909-026-03447-y","url":null,"abstract":"<div>In this study, we report direct force measurements of the temperature-dependent macroscopic phonon angular momentum, using a fiber-optic interferometer and a torsional crystal oscillator. An oscillating magnetic field was applied to an insulating ferromagnet attached to a single-crystal silicon double-torsional oscillator. By the Einstein-de Haas effect, oscillator displacement measurements between low temperatures and those closer to the Debye temperature allow observation of the changing phonon angular momentum. A force change of approximately 60 nN was detected between 77 K and 300 K for a 0.3 mm(^3) MgZn ferrite sample, in fair agreement with theoretical predictions. Our oscillator, with a thermal noise limit on the order of 10(^{-12}) N/(sqrt{text {Hz}}), allows the possibility of high-accuracy detection. Competing effects were minimized; for example, induced eddy current momentum can overwhelm the phonon effect for metallic ferromagnets, and careful temperature-dependent force calibrations were required.</div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03447-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148615140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0