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Bulletin of the Russian Academy of Sciences: Physics最新文献

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Relaxation of Multiple-Quantum Coherences in Dipolar Coupled 1H Spin Pairs in Gypsum 石膏中双极性耦合 1H 自旋对中的多量子相干弛豫
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707153
E. B. Fel’dman, E. I. Kuznetsova, A. V. Fedorova, K. V. Panicheva, S. G. Vasil’ev, A. I. Zenchuk
{"title":"Relaxation of Multiple-Quantum Coherences in Dipolar Coupled 1H Spin Pairs in Gypsum","authors":"E. B. Fel’dman,&nbsp;E. I. Kuznetsova,&nbsp;A. V. Fedorova,&nbsp;K. V. Panicheva,&nbsp;S. G. Vasil’ev,&nbsp;A. I. Zenchuk","doi":"10.1134/S1062873824707153","DOIUrl":"10.1134/S1062873824707153","url":null,"abstract":"<p>The evolution and relaxation of MQ NMR coherences on the preparation period were investigated experimentally on a single crystal of gypsum, CaSO<sub>4</sub>·2H<sub>2</sub>O. The theory describing the dynamics of MQ coherences on the preparation period of MQ experiment for a pair of spins was developed based on the Lindblad master equation. This theory predicts the appearance of MQ coherences of only zeroth and second orders, oscillatory exchange of their intensities and exponential decay with increasing of the preparation time. The proposed theory describes the experimental data well. It is shown that the frequency of oscillations depends on the orientation of the crystal in the external magnetic field and determined by the dipolar coupling between protons of the water molecules contained in the gypsum crystal. The relaxation time of MQ coherences of zeroth and second orders, <i>T</i><sub>r</sub> = 150 ± 15 μs, were independent of the crystal orientation, which suggest a common source of relaxation due to the dipole-dipole interactions with protons surrounding water molecule.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1099 - 1106"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Synthesis, Magnetic Properties, and Modeling of Magnetization Reversal of an Artificial Antiferromagnet Based on L10-PdFe 基于 L10-PdFe 的人工反铁磁体的合成、磁性和磁化反转建模
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707104
M. V. Pasynkov, I. V. Yanilkin, A. I. Gumarov, A. V. Petrov, L. R. Tagirov, R. V. Yusupov
{"title":"Synthesis, Magnetic Properties, and Modeling of Magnetization Reversal of an Artificial Antiferromagnet Based on L10-PdFe","authors":"M. V. Pasynkov,&nbsp;I. V. Yanilkin,&nbsp;A. I. Gumarov,&nbsp;A. V. Petrov,&nbsp;L. R. Tagirov,&nbsp;R. V. Yusupov","doi":"10.1134/S1062873824707104","DOIUrl":"10.1134/S1062873824707104","url":null,"abstract":"<p>The static magnetic properties were experimentally studied and magnetization reversal was modeled in an epitaxial thin film of the <i>L</i>1<sub>0</sub> phase of the PdFe compound and the PdFe/W/PdFe heterostructure on MgO (001) substrates. It was shown that the PdFe/W/PdFe heteroepitaxial structure at an α-W layer thickness of ∼0.7 nm is an artificial antiferromagnet with perpendicular magnetic anisotropy and an exchange integral of <span>(J simeq 1.7 times {{10}^{{ - 3}}},,{text{J/}}{{{text{m}}}^{2}})</span>. Micromagnetic modeling of the equilibrium domain structure and its evolution in an external magnetic field made it possible to satisfactorily describe the magnetization reversal curve of the studied thin-film heterostructure.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1073 - 1076"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Comparative Study of the Structure and Electromagnetic Characteristics of Manganites Doped with Cation Pairs (Fe,Zn), (Fe,Co), and (Fe,Mg) 掺杂阳离子对（Fe,Zn）、（Fe,Co）和（Fe,Mg）的锰矿的结构和电磁特性比较研究
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S106287382470727X
A. G. Badelin, V. K. Karpasyuk, S. Kh. Estemirova
{"title":"Comparative Study of the Structure and Electromagnetic Characteristics of Manganites Doped with Cation Pairs (Fe,Zn), (Fe,Co), and (Fe,Mg)","authors":"A. G. Badelin,&nbsp;V. K. Karpasyuk,&nbsp;S. Kh. Estemirova","doi":"10.1134/S106287382470727X","DOIUrl":"10.1134/S106287382470727X","url":null,"abstract":"<p>The influence of the configuration of ions (Zn<sup>2+</sup>(3<i>d</i><sup>10</sup>), Co<sup>2+</sup>(3<i>d</i><sup>7</sup>), Co<sup>3+</sup>(3<i>d</i><sup>6</sup>), Mg<sup>2+</sup>(2<i>p</i><sup>6</sup>)) replacing manganese in La–Sr manganites on crystal lattice parameters, magnetization, Curie point, semiconductor-metal transition and magnetoresistance has been established. The composition with cobalt in the state of Co<sup>3+</sup>(3<i>d</i><sup>6</sup>) has the highest values of magnetic parameters, and Mg-containing manganite has the lowest values, but it exhibits the maximum magnitude of magnetoresistance.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1172 - 1175"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Kinetics and Quantum Trajectories of Luminescence Intensity of Single Color Centers in Sodium Fluoride Crystals 氟化钠晶体中单色中心发光强度的动力学和量子轨迹
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707049
E. A. Protasova, A. L. Rakevich, E. F. Martynovich
{"title":"Kinetics and Quantum Trajectories of Luminescence Intensity of Single Color Centers in Sodium Fluoride Crystals","authors":"E. A. Protasova,&nbsp;A. L. Rakevich,&nbsp;E. F. Martynovich","doi":"10.1134/S1062873824707049","DOIUrl":"10.1134/S1062873824707049","url":null,"abstract":"<p>Single color centers in sodium fluoride crystals were studied for the first time. The quantum trajectories of the intensity of three types of luminescence centers emitting in the visible region of the spectrum were observed, one of which is the <span>({text{F}}_{3}^{ + })</span> center. The quantum trajectories were determined to be flickering. Their flickering is caused by transitions of the centers from the excited singlet state to the triplet state and, further, to the ground singlet state. The average lifetime of the ground triplet state of <span>({text{F}}_{3}^{ + })</span> centers as measured from the quantum trajectories of luminescence of single centers is 1.9 s, which coincides with the results of past measurements of the decay kinetics of triplet luminescence of an ensemble of <span>({text{F}}_{3}^{ + })</span> centers.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1041 - 1045"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Spectral Luminescent Properties of Alkaline Earth Fluoride Crystals Implanted with Silver Ions 植入银离子的碱土氟化物晶体的光谱发光特性
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707062
V. L. Paperny, A. A. Chernykh, A. S. Ishchenko, S. V. Murzin, A. S. Myasnikova, R. Yu. Shendrik, E. F. Martynovich, V. P. Dresvyanskiy
{"title":"Spectral Luminescent Properties of Alkaline Earth Fluoride Crystals Implanted with Silver Ions","authors":"V. L. Paperny,&nbsp;A. A. Chernykh,&nbsp;A. S. Ishchenko,&nbsp;S. V. Murzin,&nbsp;A. S. Myasnikova,&nbsp;R. Yu. Shendrik,&nbsp;E. F. Martynovich,&nbsp;V. P. Dresvyanskiy","doi":"10.1134/S1062873824707062","DOIUrl":"10.1134/S1062873824707062","url":null,"abstract":"<p>Spectral and kinetic characteristics of photoluminescence of BaF<sub>2</sub> and SrF<sub>2</sub> crystals implanted with high-energy (∼100 keV) Ag ions were studied. The photoluminescence spectra of both crystals have a similar structure, in which three components are observed with maxima in the wavelength ranges 500–550, 600–670, and 760–770 nm. The positions of the maxima depend on the material of the matrix and the excitation wavelength. The kinetic curves of luminescence decay also exhibit three components with characteristic decay times of ≤1, about 4, and 13–15 ns.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1051 - 1054"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nonlocal Effects in the Method of Integral Equations of the Theory of Liquids 液体理论积分方程法中的非局部效应
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707001
Yu. V. Agrafonov, I. S. Petrushin
{"title":"Nonlocal Effects in the Method of Integral Equations of the Theory of Liquids","authors":"Yu. V. Agrafonov,&nbsp;I. S. Petrushin","doi":"10.1134/S1062873824707001","DOIUrl":"10.1134/S1062873824707001","url":null,"abstract":"<p>The Ornstein–Zernike integral equations for thermodynamically equilibrium liquids are considered, taking into account irreducible diagrams. An algorithm for calculating the first irreducible diagram is formulated for a spatially homogeneous fluid. For liquids bordering a solid surface, an equation is obtained that implicitly considers all irreducible diagrams.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1017 - 1021"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Comparison of the Nuclear Spin Relaxation in Magnetic Cu(II) and Nonmagnetic Ni(II)-(bis)oxamato Complexes 磁性 Cu(II) 和非磁性 Ni(II)-(双)草氨酸配合物的核自旋弛豫比较
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707128
Yu. V. Slesareva, E. L. Vavilova, Yu. E. Kandrashkin, R. B. Zaripov
{"title":"Comparison of the Nuclear Spin Relaxation in Magnetic Cu(II) and Nonmagnetic Ni(II)-(bis)oxamato Complexes","authors":"Yu. V. Slesareva,&nbsp;E. L. Vavilova,&nbsp;Yu. E. Kandrashkin,&nbsp;R. B. Zaripov","doi":"10.1134/S1062873824707128","DOIUrl":"10.1134/S1062873824707128","url":null,"abstract":"<p>The electronic system of molecular-based magnets is promising for use in quantum computing devices. Magnetic resonance techniques are used for magnetization manipulation and coherence tracking. The complexes [<i>n</i>-Bu<sub>4</sub>N]<sub>2</sub>[Cu(opba)] and [<i>n</i>-Bu<sub>4</sub>N]<sub>2</sub>[Ni(opba)] have been studied by <sup>1</sup>H NMR technique using different pulse protocols. It is shown that the interpulse delay shift and phase cycling approaches are applicable in <sup>1</sup>H NMR, but it’s not as efficient as they are in EPR. Since many nuclei positions completely suppress the unwanted echo contribution, the subensembles including the longitudinal magnetization evolution should be considered.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1082 - 1088"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Structure, Conformation and Self-Association of the Alumolanes and Borolanes Spiro Fused with Terpenes 与萜烯类化合物融合的铝烷烃和硼烷烃螺的结构、构象和自我关联
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707165
T. V. Tyumkina, S. M. Idrisova, R. R. Nurislamova, L. I. Tulyabaeva
{"title":"Structure, Conformation and Self-Association of the Alumolanes and Borolanes Spiro Fused with Terpenes","authors":"T. V. Tyumkina,&nbsp;S. M. Idrisova,&nbsp;R. R. Nurislamova,&nbsp;L. I. Tulyabaeva","doi":"10.1134/S1062873824707165","DOIUrl":"10.1134/S1062873824707165","url":null,"abstract":"<p>The <sup>1</sup>H, <sup>13</sup>C, <sup>11</sup>B and <sup>27</sup>Al NMR signals of several polycyclic spiro-fused terpene-alumolanes and spiro-fused terpene-borolane were assigned. Aluminolanes form the dimers predominantly at the cyclic Al(1)–C(5) bond in toluene according to DFT calculations of Gibbs free energy of dimerization reaction and <sup>27</sup>Al NMR spectroscopy (δ<sub>Al</sub> ∼ 150–159 ppm). In tetrahydrofuran, the complexation of a solvent molecule on aluminolane metal atom proceeds, as evidenced by the shift of signals in the <sup>27</sup>Al NMR spectra to δ<sub>Al</sub> ∼ 174–178 ppm. The signals of methylene groups located in α-position relative to aluminum and boron atoms are broadened or not observed in <sup>1</sup>H and <sup>13</sup>C NMR spectra because of quadrupole relaxation of these heteroatoms. Theoretical conformational analysis showed that the energy barrier for inversion of terpene derivatives of spiro-fused 1-fluoroborolane is lower compared to those of spiro-fused 1-ethylalumolanes.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1107 - 1114"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Superconducting Properties of a Co1/Cu/Co2/Cu/Pb Heterostructure on a PMN‒PT Piezoelectric Substrate PMN-PT 压电衬底上的 Co1/Cu/Co2/Cu/Pb 异质结构的超导特性
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707207
A. A. Kamashev, A. A. Validov, S. A. Bol’shakov, N. N. Garif’yanov, I. A. Garifullin
{"title":"Superconducting Properties of a Co1/Cu/Co2/Cu/Pb Heterostructure on a PMN‒PT Piezoelectric Substrate","authors":"A. A. Kamashev,&nbsp;A. A. Validov,&nbsp;S. A. Bol’shakov,&nbsp;N. N. Garif’yanov,&nbsp;I. A. Garifullin","doi":"10.1134/S1062873824707207","DOIUrl":"10.1134/S1062873824707207","url":null,"abstract":"<p>The authors study the effect a PMN‒PT ([Pb(Mg<sub>1/3</sub>Nb<sub>2/3</sub>)O<sub>3</sub>]<sub>0.7</sub>‒[PbTiO<sub>3</sub>]<sub>0.3</sub>) piezoelectric substrate has on the superconducting properties of a Co1/Cu/Co2/Cu/Pb thin-film heterostructure. A change in temperature <i>T</i><sub>c</sub> of the superconducting transition in electric and magnetic fields is detected. The maximum difference between <i>T</i><sub>c</sub> values is found to be 15 mK in an applied electric field of 1 kV/cm. In an external magnetic field, the greatest <i>T</i><sub>c</sub> difference is more than 80 mK upon changing the mutual orientation of the magnetizations of ferromagnetic layers from collinear to perpendicular.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1131 - 1134"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Synthesis and Magnetic Properties of Fe1.1Ga0.9O3, Measured According to Electron Spin Resonance 利用电子自旋共振测量 Fe1.1Ga0.9O3 的合成和磁性能
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2024-08-19 DOI: 10.1134/S1062873824707220
I. V. Yatsyk, R. M. Eremina, E. M. Moshkina, R. G. Batulin, A. V. Shestakov
{"title":"Synthesis and Magnetic Properties of Fe1.1Ga0.9O3, Measured According to Electron Spin Resonance","authors":"I. V. Yatsyk,&nbsp;R. M. Eremina,&nbsp;E. M. Moshkina,&nbsp;R. G. Batulin,&nbsp;A. V. Shestakov","doi":"10.1134/S1062873824707220","DOIUrl":"10.1134/S1062873824707220","url":null,"abstract":"<p>The authors study the formation of crystals of Fe-Ga oxides and Fe–Ga–Cu borates in a multicomponent flux system based on Bi<sub>2</sub>Mo<sub>3</sub>O<sub>12</sub>–Na<sub>2</sub>B<sub>4</sub>O<sub>7</sub>. The Curie–Weiss temperature (θ<sub>CW</sub> = 289 K) and the temperature of the ferrimagnet–paramagnet phase transition (<i>T</i><sub>C</sub> = 288 K) are determined from the electron spin resonance (ESR) spectrum and the magnetization of an Fe<sub>1.1</sub>Ga<sub>0.9</sub>O<sub>3</sub> single crystal, depending on temperature. Lines of spin-wave resonance are observed in the spectrum of magnetic resonance in the ordered phase.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 7","pages":"1140 - 1147"},"PeriodicalIF":0.48,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142186494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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