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Nuclear Magnetic Resonance Evidence for a Pseudogap in a Pb-Doped Bi:2201 Single Crystal 掺铅Bi:2201单晶赝隙的核磁共振证据
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-15 DOI: 10.1134/S0021364025607109
O. M. Vyaselev
{"title":"Nuclear Magnetic Resonance Evidence for a Pseudogap in a Pb-Doped Bi:2201 Single Crystal","authors":"O. M. Vyaselev","doi":"10.1134/S0021364025607109","DOIUrl":"10.1134/S0021364025607109","url":null,"abstract":"<p>A <sup>63</sup>Cu nuclear magnetic resonance (NMR) study of a Pb-doped Bi:2201 system, Bi<sub>1.6</sub>Pb<sub>0.4</sub>Sr<sub>2.05</sub>CuO<sub><i>y</i></sub>, is presented. The temperature dependencies of the NMR peak shift and the nuclear spin–lattice relaxation (SLR) rate reveal the pseudogap that opens near <span>(T{text{*}} = 60)</span> K, significantly above the superconducting critical temperature <span>({{T}_{{text{c}}}} simeq 9 )</span> K at the NMR experiment field, 7 T oriented <b>H</b> || <i>c</i>. The noticeable disparity between <i>T</i><sub>c</sub> and <i>T</i> * and the behavior of Cu SLR at <span>(T &gt; T{text{*}})</span> imply the underdoped state of the studied system. A relatively weak effect of the magnetic field on the superconductivity evidenced from small (<span>( approx )</span>7 K) shift of the zero-field <i>T</i><sub>c0</sub> = (16 ± 1) K under the applied 7 T field suggests high upper critical field, <i>H</i><sub>c2</sub>, unusual for compounds with as low <i>T</i><sub>c0</sub>.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"122 2","pages":"92 - 96"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025607109.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144990629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Estimation of the Intergranular Transparency of Diffusive Superconducting Films from the Shape of the Density of States of the Abrikosov Vortex 从Abrikosov涡的态密度形状估计扩散超导膜的晶间透明度
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-15 DOI: 10.1134/S0021364025607419
M. M. Khapaev, M. Yu. Kupriyanov, A. A. Golubov, V. S. Stolyarov
{"title":"Estimation of the Intergranular Transparency of Diffusive Superconducting Films from the Shape of the Density of States of the Abrikosov Vortex","authors":"M. M. Khapaev,&nbsp;M. Yu. Kupriyanov,&nbsp;A. A. Golubov,&nbsp;V. S. Stolyarov","doi":"10.1134/S0021364025607419","DOIUrl":"10.1134/S0021364025607419","url":null,"abstract":"<p>A technique has been developed for the evaluation of the transparency of grain boundaries in polycrystalline superconducting films. The model is founded upon a numerical algorithm for calculating the density of states of an Abrikosov vortex located in the center of a cylindrical granule, separated from the main superconducting matrix by a boundary with finite transparency. The present study calculates the dependences of the gap difference in the density of states on both sides of the boundary and uses this difference to estimate the transparency of the interface.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"122 2","pages":"116 - 120"},"PeriodicalIF":1.3,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025607419.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144990632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Coherent Transition Radiation of a Hollow Bessel Beam 空心贝塞尔光束的相干跃迁辐射
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S0021364025606475
D. Yu. Sergeeva, A. A. Tishchenko
{"title":"Coherent Transition Radiation of a Hollow Bessel Beam","authors":"D. Yu. Sergeeva,&nbsp;A. A. Tishchenko","doi":"10.1134/S0021364025606475","DOIUrl":"10.1134/S0021364025606475","url":null,"abstract":"<p>The transition radiation from a relativistic electron Bessel beam has been theoretically investigated. The form factor determining the possibility of realizing intense coherent radiation from a Bessel beam has been calculated. The results for the hollow Bessel and Gaussian beams are compared. A target in the form of a two-dimensional planar photonic crystal is considered to analyze the transition radiation characteristics.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"759 - 765"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025606475.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145160523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Flow of Dilute Polymer Solutions Through a Channel with a Large Obstacle at Small Reynolds Numbers 稀聚合物溶液在小雷诺数下通过大障碍物通道的流动
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S002136402560613X
I. Yu. Kardash, S. V. Filatov, A. A. Levchenko
{"title":"Flow of Dilute Polymer Solutions Through a Channel with a Large Obstacle at Small Reynolds Numbers","authors":"I. Yu. Kardash,&nbsp;S. V. Filatov,&nbsp;A. A. Levchenko","doi":"10.1134/S002136402560613X","DOIUrl":"10.1134/S002136402560613X","url":null,"abstract":"<p>The addition of even small quantities of high-molecular-weight polymers can significantly alter the rheological properties of a fluid. When subjected to shear flow, polymers stretch, imparting elasticity to the fluid. At low Reynolds numbers, elastic forces may dominate over inertial effects. In this study, the pressure difference between two points in the channel and the average mass flow of fluid (with the average velocity <span>(langle {v}rangle )</span>) have been measured in an obstacle-laden channel (channel with a width of 2.5 mm, a height of 1 mm and a vertically oriented cylindrical obstacle with a diameter <span>(d = 1)</span> mm in the center of the channel). Beyond the critical Weissenberg number Wi <span>( = lambda langle {v}rangle {text{/}}d)</span> (where <span>(lambda )</span> is the longest relaxation time), the friction factor (calculated from the pressure difference and average flow) rose above laminar flow values which is concurrent with enhanced fluctuations in the pressure differential between two measurement points. Spectral analysis of pressure fluctuation dynamics has been performed to characterize these effects. The results demonstrate that polymers achieve a highly stretched conformation, reflected in pronounced viscoelastic behavior.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"783 - 788"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Structural Transition in Dodecaborides According to NMR in LuB12 LuB12中十二硼化物的核磁共振结构转变
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S0021364025606499
O. M. Vyaselev, A. A. Gippius, N. E. Sluchanko
{"title":"Structural Transition in Dodecaborides According to NMR in LuB12","authors":"O. M. Vyaselev,&nbsp;A. A. Gippius,&nbsp;N. E. Sluchanko","doi":"10.1134/S0021364025606499","DOIUrl":"10.1134/S0021364025606499","url":null,"abstract":"<p>Analysis of the nuclear magnetic resonance linewidth and spin-lattice relaxation rate of <sup>175</sup>Lu in LuB<sub>12</sub> assumes a structural transition at <i>T</i>*~150 K into a state with a long-range ferrodistortive order of lattice distortions caused by the cooperative Jahn–Teller effect. The reported experimental facts imply this transition to be characteristic of other rare-earth dodecaborides.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"789 - 793"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025606499.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Suppression of the Magnetic Transition in Ultrasmall ϵ-Fe2O3 Nanoparticles: the Size Effect from Nuclear Forward Scattering Data 抑制超小ϵ-Fe2O3纳米颗粒的磁跃迁：核正向散射数据的尺寸效应
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S0021364025606396
Yu. V. Knyazev, D. A. Balaev, A. A. Dubrovskiy, S. V. Semenov, V. L. Kirillov, O. N. Martyanov
{"title":"Suppression of the Magnetic Transition in Ultrasmall ϵ-Fe2O3 Nanoparticles: the Size Effect from Nuclear Forward Scattering Data","authors":"Yu. V. Knyazev,&nbsp;D. A. Balaev,&nbsp;A. A. Dubrovskiy,&nbsp;S. V. Semenov,&nbsp;V. L. Kirillov,&nbsp;O. N. Martyanov","doi":"10.1134/S0021364025606396","DOIUrl":"10.1134/S0021364025606396","url":null,"abstract":"<p>The features of the magnetic structure of ultrasmall <span>(epsilon )</span>-Fe<sub>2</sub>O<sub>3</sub> nanoparticles have been studied by the nuclear forward scattering technique using synchrotron radiation. The sample consists of isolated <span>(epsilon )</span>-Fe<sub>2</sub>O<sub>3</sub> nanoparticles with an average size of <span>(langle drangle = 3.8)</span> nm immobilized in a SiO<sub>2</sub> xerogel matrix. The time-domain spectra have been measured in the temperature range of 4–300 K in zero external magnetic field and field <span>(H = 4)</span> T applied in the longitudinal direction. The character of the change in the hyperfine field <i>H</i><sub>hf</sub> as a function of the external magnetic field is the same in the entire temperature range: unlike large <span>(epsilon )</span>-Fe<sub>2</sub>O<sub>3</sub> particles, a monotonic increase in <i>H</i><sub>hf</sub> is observed in the external field. These results indicate that there is no magnetic transition in the temperature range of 80–150 K for ultrasmall (smaller than <span>( approx )</span>9 nm) <span>(epsilon )</span>-Fe<sub>2</sub>O<sub>3</sub> particles, and the magnetic structure is noncollinear in the range of 4–300 K.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"800 - 805"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025606396.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Angular Distribution of the Intensity of a Mid-Infrared Femtosecond Radiation Source in a Nonlinear Crystal with a Signal Wave Formed in a Filament in a Gas 中红外飞秒辐射源在气体中灯丝形成信号波的非线性晶体中强度的角分布
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S0021364025605743
I. O. Kinyaevskiy, M. V. Ionin, A. V. Koribut, Yu. M. Andreev
{"title":"Angular Distribution of the Intensity of a Mid-Infrared Femtosecond Radiation Source in a Nonlinear Crystal with a Signal Wave Formed in a Filament in a Gas","authors":"I. O. Kinyaevskiy,&nbsp;M. V. Ionin,&nbsp;A. V. Koribut,&nbsp;Yu. M. Andreev","doi":"10.1134/S0021364025605743","DOIUrl":"10.1134/S0021364025605743","url":null,"abstract":"<p>The divergence of mid-infrared radiation obtained by difference frequency generation of femtosecond titanium–sapphire laser pulses in a 2-mm-thick nonlinear HgGa<sub>2</sub>S<sub>4</sub> crystal has been measured. At a pump radiation aperture of 2.8 mm, the output radiation divergence is 5.2 and 9.2 mrad at wavelengths of 7.2 and 10.5 μm, respectively. It has been shown experimentally that the angular distribution of the difference frequency radiation intensity differs significantly from the Gaussian one and the divergence of the central maximum is determined as in Fraunhofer diffraction on a circular hole with a radius equal to the radius of the interaction region.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"778 - 782"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Effect of Non-Stoichiometry of High-Temperature Superconductors of the Composition Gd1 + xBa2 – yCu3O7 – δ on Vortex Pinning and on the Vortex Liquid–Glass Phase Transition Gd1 + xBa2 - yCu3O7 - δ高温超导体非化学计量学对涡旋钉钉和涡旋液-玻璃相变的影响
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S0021364025606116
B. I. Massalimov, V. A. Vlasenko, A. R. Prishchepa, P. N. Degtyarenko, E. M. Ivanova, A. V. Sadakov
{"title":"Effect of Non-Stoichiometry of High-Temperature Superconductors of the Composition Gd1 + xBa2 – yCu3O7 – δ on Vortex Pinning and on the Vortex Liquid–Glass Phase Transition","authors":"B. I. Massalimov,&nbsp;V. A. Vlasenko,&nbsp;A. R. Prishchepa,&nbsp;P. N. Degtyarenko,&nbsp;E. M. Ivanova,&nbsp;A. V. Sadakov","doi":"10.1134/S0021364025606116","DOIUrl":"10.1134/S0021364025606116","url":null,"abstract":"<p>High-temperature superconducting film samples of the non-stoichiometric composition Gd<sub>1+<i>x</i></sub>Ba<sub>2–<i>y</i></sub>Cu<sub>3</sub>O<sub>7–δ</sub> have been systematically studied. The measured <i>R</i>(<i>T</i>) curves in magnetic fields have demonstrated a sharp change in the nature of pinning with the field, which indicates a possible phase transition of the pinned vortex system from a three-dimensional state to a quasi-two-dimensional one. The vortex structure pinning has been described within the thermally activated flux flow model. The analysis of the dependence of the vortex activation energy <i>U</i><sub>0</sub>(<i>B</i>) on the magnetic field has indicated that the influence of thermal fluctuations on the vortex system in non-stoichiometric high-temperature superconductors Gd<sub>1+<i>x</i></sub>Ba<sub>2–<i>y</i></sub>Cu<sub>3</sub>O<sub>7–δ</sub> is smaller than that in stoichiometric superconductors of a similar composition.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"794 - 799"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Quantum Entanglement of Photon-Added Coherent States on a Beam Splitter 分束器上添加光子相干态的量子纠缠
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S0021364025605986
D. N. Makarov
{"title":"Quantum Entanglement of Photon-Added Coherent States on a Beam Splitter","authors":"D. N. Makarov","doi":"10.1134/S0021364025605986","DOIUrl":"10.1134/S0021364025605986","url":null,"abstract":"<p>The study of new quantum states and methods for their generation is an important part of the current development of quantum technologies. One of the most important characteristics of such states is their quantum entanglement. Photon-added coherent states, which are defined as <span>({text{|}}alpha ,nrangle = {{mathcal{N}}_{n}}{{({{hat {a}}^{dag }})}^{n}}{text{|}}alpha rangle )</span>, where <span>({{mathcal{N}}_{n}})</span> is the normalization constant, <span>({text{|}}alpha rangle )</span> is the coherent state, <span>({{hat {a}}^{dag }})</span> is the creation operator, and <i>n</i> is the number of added photons, have been introduced relatively recently. The quantum entanglement of such states passing through a beam splitter has been considered for the first time in this work. A simple analytical representation of the wavefunction at the outputs of the beam splitter has been found and the quantum entanglement of the resulting two-qubit states has been considered. It has been shown that new quantum states have good prospects for their use in quantum technologies.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"806 - 810"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025605986.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
Preparation of Multiparticle Greenberger–Horne–Zeilinger States on 171Yb+ Ions for Frequency Standards 171Yb+离子在频率标准上制备多粒子greenberger - horn - zeilinger态
IF 1.3 4区 物理与天体物理
JETP Letters Pub Date : 2025-07-14 DOI: 10.1134/S002136402560630X
A. E. Korolkov, I. V. Zalivako, A. S. Borisenko, V. N. Smirnov, P. A. Kamenskikh, I. A. Semerikov, K. Yu. Khabarova, N. N. Kolachevsky
{"title":"Preparation of Multiparticle Greenberger–Horne–Zeilinger States on 171Yb+ Ions for Frequency Standards","authors":"A. E. Korolkov,&nbsp;I. V. Zalivako,&nbsp;A. S. Borisenko,&nbsp;V. N. Smirnov,&nbsp;P. A. Kamenskikh,&nbsp;I. A. Semerikov,&nbsp;K. Yu. Khabarova,&nbsp;N. N. Kolachevsky","doi":"10.1134/S002136402560630X","DOIUrl":"10.1134/S002136402560630X","url":null,"abstract":"<p>Greenberger–Horne–Zeilinger states on two to eight qubits in a chain of ten <sup>171</sup>Yb<sup>+</sup> ions in a linear Paul trap has been prepared by executing a sequence of one- and two-qubit operations on the corresponding ions. The obtained states have been analyzed and their fidelity for the Greenberger–Horne–Zeilinger state on eight qubits has been estimated at (58.9 ± 0.6)%. The expected increase in the sensitivity of parity oscillations as a function of the phase of the probe laser pulse has also been demonstrated. This result is an important step towards the creation of a multiparticle ytterbium ion optical clock with frequency averaging according to the law 1/<i>N</i> in contrast to the slower law <span>(1{text{/}}sqrt N )</span> for an ensemble of independent particles in the case where decoherence is dominated by spontaneous decay.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 10","pages":"811 - 817"},"PeriodicalIF":1.3,"publicationDate":"2025-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S002136402560630X.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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
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