Journal of Low Temperature Physics最新文献

{"title":"Nonclassical Moment of Inertia and Revival Time from the Interaction of the Induced Electric Dipole Moment of a Neutral Particle with Nonuniform Electric and Magnetic Fields","authors":"K. Bakke","doi":"10.1007/s10909-026-03451-2","DOIUrl":"10.1007/s10909-026-03451-2","url":null,"abstract":"<div><p>With nonuniform crossed electric and magnetic fields inside a long nonconducting cylinder, we show that a non-null nonclassical moment of inertia (at zero temperature) and revival time can be obtained for <i>s</i>-wave from the interaction of these fields with the induced electric dipole moment of a neutral particle combined with rotation.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03451-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614084","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}

{"title":"Experimental Challenges in Determining Heat Transfer Efficiency Scaling in Highly Turbulent Cryogenic Rayleigh–Bénard Convection","authors":"P. Urban,&nbsp;V. Musilová,&nbsp;P. Hanzelka,&nbsp;T. Králík,&nbsp;M. Macek,&nbsp;L. Skrbek","doi":"10.1007/s10909-026-03439-y","DOIUrl":"10.1007/s10909-026-03439-y","url":null,"abstract":"<div><p>Cryogenic Rayleigh–Bénard convection (RBC) at very high Rayleigh numbers (Ra) serves as a key system for understanding buoyancy-driven industrial and large-scale natural flows and for testing theories of turbulent convective heat transport. The central measured response is the Nusselt number (Nu), which quantifies the convective heat transfer efficiency, i.e., the enhancement of heat transport relative to the purely conductive state. Cryogenic helium experiments allow one to reach extremely high Ra under well-controlled laboratory conditions; however, interpretation of the resulting Nu(Ra) scalings remains sensitive to non-Oberbeck–Boussinesq (NOB) effects, experimental uncertainties, and corrections that must be applied to raw data. We present an analysis of experimental uncertainties and data correction procedures applicable to cryogenic RBC experiments, specifically to those performed in the present, newly built cylindrical RBC cell in Brno. For a representative set of <span>(^{4})</span>He working points in the <i>p</i>–<i>T</i> diagram, we examine how the evaluated Nu(Ra) dependence is affected by measurement uncertainties, corrections for the adiabatic temperature gradient, parasitic heat leaks, finite thermal conductivity of the plates and sidewalls, and by the choice of thermophysical property database used to determine the relevant properties of <span>(^{4})</span>He at the selected working points. The analysis shows that uncertainties and offset corrections associated with the temperature difference across the cell have the strongest local impact on the evaluated Nu(Ra) dependence, while sidewall corrections and the choice of thermophysical property database mainly affect the global scaling behavior. Our study highlights the necessity of rigorous uncertainty and correction analysis when assessing experimental evidence for a transition to the ultimate regime of RBC, since apparent changes in scaling may also arise from NOB effects and experimental imperfections.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148614008","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}

{"title":"Numerical Study on Phase Shifter Effects on Heat Transfer, Flow, and Entropy Generation in Pulse Tube Refrigerators","authors":"Yu Yan,&nbsp;Longyu Yang,&nbsp;Yu Liu,&nbsp;Bingcheng Wang,&nbsp;Zheng Cui,&nbsp;Wei Shao","doi":"10.1007/s10909-026-03445-0","DOIUrl":"10.1007/s10909-026-03445-0","url":null,"abstract":"<div><p>The hot end terminal section of a pulse tube refrigerator fundamentally shapes its internal energy transport and irreversibility. In this work, the roles of the terminal compressible volume and the high resistance structure are decoupled using three 2D axisymmetric CFD models. Under no-load conditions, the inertance pulse tube refrigerator achieves effective cooling to 84 K, whereas the model with only the high resistance structure or only the terminal compressible volume shows much poorer cooling performance. Detailed thermodynamic analyses are performed for the pulse tube, regenerator, and cold heat exchanger, with emphasis on cooling behavior, pressure–volume (PV) power and enthalpy flow conversion, and entropy generation. The results show that the main role of terminal resistance is to reduce the losses associated with viscous dissipation in the pulse tube and the pressure drop losses in the regenerator. In contrast, the terminal compressible volume mainly helps maintain stable periodic oscillating flow in the pulse tube and provides a certain phase adjustment effect, thereby improving PV power transmission. Proper matching between these two effects can effectively reduce the irreversible losses of the system and improve energy utilization efficiency. In comparison, the continuous phase shifting capability of the inertance tube plays a more critical role in increasing the transmissible PV power of the system. The calculation results at a cold-end temperature of 120 K further show that the present study can provide theoretical guidance for the optimal design of the phase shifter and the improvement of cooling performance in inertance pulse tube refrigerators.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466076","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}

{"title":"Effect of Fe Substitution at the Y Site in YBa2Cu3O7−δ Superconductor","authors":"Juan Camilo Rincón Fajardo,&nbsp;Fernanda Andrea Páez-Reyes,&nbsp;Eliana Marcela Vargas Pineda,&nbsp;David A. Landínez Téllez,&nbsp;Jairo Roa-Rojas","doi":"10.1007/s10909-026-03438-z","DOIUrl":"10.1007/s10909-026-03438-z","url":null,"abstract":"<div><p>This work investigates the effect of low-level Fe incorporation (x ≤ 0.009) in YBa₂Cu₃O_7−δ, nominally at the Y site, on the structural and superconducting properties. X-ray diffraction confirms preservation of the orthorhombic phase with subtle changes in lattice parameters, suggesting local distortions and modifications in oxygen ordering. Resistivity measurements reveal a two-stage superconducting transition associated with intragranular pairing and intergranular coherence, consistent with weak-link behavior in polycrystalline samples. A slight maximum in characteristic temperatures is observed at x ≈ 0.2–0.3%, followed by a decrease at higher Fe content. Magnetic measurements show a reduction of the diamagnetic response and irreversibility temperature with doping. The results indicate competition between weakened intergranular coupling and enhanced intragranular vortex pinning induced by Fe-related defects, highlighting a low-doping regime for tuning superconducting performance.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03438-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466078","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}

{"title":"Temperature Dependence of Superconducting State in a Nano-sized Dirty superconductor","authors":"Masaru Kato,&nbsp;Terukazu Nishizaki","doi":"10.1007/s10909-026-03433-4","DOIUrl":"10.1007/s10909-026-03433-4","url":null,"abstract":"<div><p>Superconductors in nano-sized shape are investigated. Superconductor and also electrons which form superconductivity have quantum nature. This means when size of superconductor is small, there appear quantum effects. The critical temperature <span>(T_c)</span> becomes higher than that of a bulk superconductor. In the extremely dirty nano-sized superconductor, the critical temperature becomes much higher than that of a clean nano-sized superconductor. This is because a part of superconducting electrons concentrates in a localized state and has a high density of states. However, if the superconducting state remains localized below <span>(T_c)</span>, resistivity may not be zero just below <span>(T_c)</span>. Therefore we investigate how this localized state of superconductivity develops with decreasing temperature below <span>(T_c)</span>. We show this localized state extends to whole superconductor just below <span>(T_c)</span>.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03433-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466077","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}

{"title":"Study of Exchange Bias Effect in LaCr1−xRuxO3 (0 ≤ x ≤ 0.3)","authors":"Biswajit Dalal,&nbsp;Babusona Sarkar","doi":"10.1007/s10909-026-03450-3","DOIUrl":"10.1007/s10909-026-03450-3","url":null,"abstract":"<div><p>The interfacial exchange interaction is key to realize exchange bias (EB) phenomenon in  materials consisting of two different magnetic phases, which have immense applications in modern era technological development. LaCrO₃ (LCO) is an antiferromagnetic (AFM) oxide, which could be utilized to perceive near room-temperature exchange bias phenomenon<b>.</b> In this work, we report an experimental investigation on the structural, magnetic and dielectric properties of LaCr_1−<i>x</i>Ru_<i>x</i>O₃ (0 ≤ <i>x</i> ≤ 0.3) through x-ray diffraction, x-ray photoelectron spectroscopy and temperature- and field-dependent magnetization and dielectric measurements. All samples are found to be crystallized in the orthorhombic structure with space group <i>Pnma</i>, and cell volume reveals a usual ionic radius related enhancement due to Ru⁴⁺ ion doping. The AFM transition of pure LCO is modified to ferromagnetic-like (FM-like) transition; while, transition temperature continuously decreases with increase in Ru doping concentration. Magnetization measurements indicate the formation of ferromagnetic cluster-glass state in <i>x</i> = 0.2 sample. We find that a tenfold increase in coercivity value for <i>x</i> = 0.1 as compared to <i>x</i> = 0, suggesting the evolution of moderate FM component. Interestingly, complex interfacial exchange interaction between host AFM matrix of LCO and induced FM phase leads to a significant EB phenomenon in the doped samples. The values of <span>(left|{H}_{EB}right|)</span> are found to be 2.61 kOe and 1.62 kOe at 200 K for <i>x</i> = 0.1 and <i>x</i> = 0.2, respectively. Moreover, EB effect can be tuned by varying the concentration of Ru dopants in LCO, which is fascinating from technological perspectives.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465828","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}

{"title":"In-Plane Field-Direction Control of Multiple-Q States and Skyrmion Crystals in a Triangular-Lattice Magnet with (D_{textrm{3d}}) Anisotropy","authors":"Satoru Hayami","doi":"10.1007/s10909-026-03442-3","DOIUrl":"10.1007/s10909-026-03442-3","url":null,"abstract":"<div><p>We investigate multiple-<i>Q</i> magnetic states in a triangular-lattice spin model with a <span>(D_{textrm{3d}})</span>-type anisotropic interaction under in-plane magnetic fields. Focusing on the interplay between anisotropy and field orientation, we examine how the magnetic phases evolve when the field is applied along two inequivalent in-plane directions. By means of simulated annealing, we identify a wide variety of field-induced phases, including both topological and non-topological multiple-<i>Q</i> states. In the strong-anisotropy regime, the skyrmion crystal with a higher topological number of two, stabilized at zero field, is transformed into the conventional skyrmion crystal with a topological number of one under increasing magnetic field. This transition occurs without a change in the principal ordering wave vectors, indicating that a subtle reorganization of the triple-<i>Q</i> components governs the change in topology. In contrast, in the weak-anisotropy regime, the magnetic behavior is sensitive to the direction of the applied magnetic field. The system eventually selects a single-<i>Q</i> state for the <i>x</i>-directional magnetic field, while it continues to reside within the multiple-<i>Q</i> states, exhibiting several distinct triple-<i>Q</i> states characterized by different intensity distributions among the symmetry-related ordering wave vectors for the <i>y</i>-directional magnetic field. These results demonstrate that the direction of an in-plane magnetic field plays an active role in selecting competing magnetic states, not only modifying phase boundaries but also controlling the topology and internal structure of the spin textures. Our findings highlight a route to manipulate multiple-<i>Q</i> states in centrosymmetric magnets through the combined effect of anisotropic interactions and field orientation.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465855","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}

{"title":"Transmissibility-Based Transfer Path Analysis of a Cryostat Interface for the CUPID Experiment","authors":"Serena D’Eramo,&nbsp;Jacopo Brunetti,&nbsp;Antonio D’Addabbo,&nbsp;Walter D’Ambrogio","doi":"10.1007/s10909-026-03440-5","DOIUrl":"10.1007/s10909-026-03440-5","url":null,"abstract":"<div><p>The CUPID (CUORE Upgrade with Particle IDentification) experiment searches for neutrinoless double beta decay using cryogenic detectors operating at milli-Kelvin temperatures. These systems are highly sensitive to mechanical vibrations introduced by cryocoolers, which can deteriorate calorimetric performance. In this work, we present the application of transmissibility-based Transfer Path Analysis (TPA) to a test cryostat devoted to CUPID. The method allows estimation of vibration transfer at structural interfaces without requiring force measurements, which are often impractical in cryogenic environments. Numerical simulations were performed at the 300 K plate interface using finite element models and component substructuring. The responses computed using transmissibility-based TPA showed excellent agreement with harmonic response simulations, validating the approach. This study establishes the basis for extending the methodology to colder stages (35 K, 3.5 K), where vibration coupling is more critical. Beyond validating the method, the results provide new insights into the dominant transfer paths at room temperature, thereby supporting the design of improved vibration isolation strategies for next-generation cryogenic detectors.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10909-026-03440-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465854","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}

{"title":"Ground States of a Rotating Spin-1 Bose-Einstein Condensate in Box Trap","authors":"Qing-Li Zhu,&nbsp;Ji-Mei Shen","doi":"10.1007/s10909-026-03441-4","DOIUrl":"10.1007/s10909-026-03441-4","url":null,"abstract":"<div><p>The ground-state phases of rotating spin-1 Bose-Einstein condensates confined in three distinct box traps are studied numerically. In circular or square box trap, the combined effects of spin-exchange interaction and rotation lead to replacement of the traditional skyrmion vortices observed in harmonic traps with coreless vortices that exhibit fourfold rotational symmetry. These vortices are nucleated readily from the trap boundary in groups of four. In a triangular box trap, a single skyrmion vortex structure is found at trap center at low rotation frequencies, while additional vortices are all nucleated from the boundary and arrange parallel to the trap edge in the form of vortex chains as the rotation frequency is further increased.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465784","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}

{"title":"Quantum multiparameter estimation of temperature and Coulomb interaction in coupled double quantum dots","authors":"Abderrahim Benaoum,&nbsp;Brahim Adnane,&nbsp;Younes Moqine,&nbsp;Aziz Khribach,&nbsp;Rachid Houça","doi":"10.1007/s10909-026-03437-0","DOIUrl":"10.1007/s10909-026-03437-0","url":null,"abstract":"<div><p>We study the quantum metrological properties of two coupled double quantum dots, where coherent tunneling and Coulomb interaction jointly govern the system dynamics. Using the quantum Fisher information framework, we evaluate the ultimate precision limits for estimating the interaction strength and temperature. We compare simultaneous and independent estimation strategies and show that parameter correlations strongly influence the achievable precision. In the simultaneous scheme, correlations may induce near-singular behavior of the quantum Fisher information matrix, leading to pronounced precision degradation in specific parameter regions. By contrast, independent estimation yields a more stable and robust precision profile. A quantitative comparison between the two strategies identifies the regimes where each approach is advantageous. Our results demonstrate that the metrological performance of coupled quantum dots is determined not only by intrinsic quantum sensitivity but also by interaction-induced correlations, providing guidance for optimizing quantum sensing protocols in solid-state nanoscale systems.</p></div>","PeriodicalId":641,"journal":{"name":"Journal of Low Temperature Physics","volume":"222 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148380654","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}