JETP Letters最新文献_第8页

Hong–Ou–Mandel Interference in Quantum Optics, Monogamy of Entanglement, Nonorthogonality, and Untrusted Nodes 量子光学中的洪欧-曼德尔干涉、纠缠的一元性、非正交性和不可信任的节点

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-24 DOI: 10.1134/S0021364024601994

S. P. Kulik, S. N. Molotkov

{"title":"Hong–Ou–Mandel Interference in Quantum Optics, Monogamy of Entanglement, Nonorthogonality, and Untrusted Nodes","authors":"S. P. Kulik, S. N. Molotkov","doi":"10.1134/S0021364024601994","DOIUrl":"10.1134/S0021364024601994","url":null,"abstract":"Quantum key distribution systems with an untrusted intermediate node described by the so-called measurement device independent (MDI) protocol have been actively studied in the last decade. In early works, it was only argued why such a quantum key distribution system ensures the security of distributed keys mentioning that the security proof of the MDI protocol, which was not presented, is similar to that for the basic Bennett‒Brassard 84 (BB84) protocol. For this reason, despite the existing experimental implementations of the MDI quantum key distribution system, physical reasons for the protocol security are still questionable. Such quantum key distribution systems provide a common key between two network nodes connected through the intermediate untrusted node, which does not require protection of the equipment on it, and an eavesdropper sees the entire operation of the equipment, including the results of the operation of photodetectors. In this work, the MDI protocol has been analyzed. It has been shown that the physical reasons for the protocol security are based on fundamental properties such as the interference of photons from different sources, monogamy of entanglement, and nonorthogonality of states. A simple and explicit derivation is given showing the equivalence of the MDI and BB84 protocols and physical reasons for the identity of the corresponding expressions for the length of the final key.","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"120 1","pages":"20 - 27"},"PeriodicalIF":1.4,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364024601994.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190810","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

Spinodal Decomposition of NbS3 Whiskers with Charge Density Waves 带有电荷密度波的 NbS3 晶须的自旋分解

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-24 DOI: 10.1134/S002136402460191X

V. P. Martovitskii, M. V. Nikitin, V. Ya. Pokrovskii

{"title":"Spinodal Decomposition of NbS3 Whiskers with Charge Density Waves","authors":"V. P. Martovitskii, M. V. Nikitin, V. Ya. Pokrovskii","doi":"10.1134/S002136402460191X","DOIUrl":"10.1134/S002136402460191X","url":null,"abstract":"The grazing X-ray diffraction study of phase-II NbS3 whiskers with charge density waves has shown that they exhibit pairs of broadened reflections from two close phases with the monoclinic angles β1 and β2 instead of single ((h0l)) peaks. The phase with the smaller monoclinic angle β1 = 95.9°–97.2° is close in lattice parameters to phase I without charge density waves. Phase II with β2 = 99.9°–100.0° has a reduced b lattice parameter along the strongest bond, which implies an increased concentration of sulfur vacancies in this phase compared to phase I. It has been concluded that the studied whiskers have underwent a spinodal decomposition with the redistribution of sulfur vacancies resulting in the alternation of phases in the (001) direction perpendicular to the layers. A satellite structure indicating the formation of a superlattice with a period of 35.2 nm in this direction is observed in the most structurally perfect whisker of phase II. The spinodal decomposition is combined with high internal stresses present in whiskers with a monoclinic lattice. The partial spinodal decomposition is also observed in some phase-I whiskers without charge density waves with the appearance of thin layers of phase IV and phase II with the monoclinic angle β = 104°. The existence of thin layers of phase II in the bulk of phase I in such samples exposed to a high-frequency voltage has been confirmed by the presence of Shapiro steps on current–voltage characteristics. Spinodal decomposition should be taken into account to describe the properties of NbS3 whiskers nominally belonging to a certain polytype.","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"120 1","pages":"38 - 45"},"PeriodicalIF":1.4,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190814","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

Phonon-Induced Spectral Line Broadening in Dye-Doped Glass in Terms of Resonant Vibrational Modes: Tetra-tert-Butylterrylene in Polyisobutylene 从共振振动模式看掺染玻璃中的声子诱导谱线展宽：聚异丁烯中的四叔丁基苯乙烯

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-24 DOI: 10.1134/S0021364024602884

A. O. Savostianov, A. V. Naumov

{"title":"Phonon-Induced Spectral Line Broadening in Dye-Doped Glass in Terms of Resonant Vibrational Modes: Tetra-tert-Butylterrylene in Polyisobutylene","authors":"A. O. Savostianov, A. V. Naumov","doi":"10.1134/S0021364024602884","DOIUrl":"10.1134/S0021364024602884","url":null,"abstract":"Previously [A.O. Savostianov, I.Yu. Eremchev, T. Plakhotnik, and A.V. Naumov, Phys. Rev. B 110, 045430 (2024)], we have shown that the zero-phonon line broadening of single tetra-tert-butylterrylene molecules embedded in the matrix of amorphous polyisobutylene is a result of coupling with resonant vibrational modes arising due to the impurity effect on the host normal modes. However, the question remained whether this model would be compatible with the extensive single-molecule spectroscopy and photon echo data previously obtained for the same host/guest system. In the present work we demonstrate the high predictive power of the resonant mode model treated in the framework of the non-perturbative theory of electron–phonon coupling, and good agreement with all experimental data. Furthermore, for single-molecule data we find an unexpectedly large dispersion of the force constants for impurity molecules. To explain this dispersion, we propose a simple microscopic model that assumes fluctuations in the distance between the impurity molecule and its nearest surroundings.","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"120 5","pages":"322 - 327"},"PeriodicalIF":1.4,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142190817","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

Theory of Composite Ramsey Sequences of Radiofrequency Pulses beyond the Rotating Wave Approximation 超越旋转波近似的射频脉冲复合拉姆齐序列理论

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-24 DOI: 10.1134/S0021364024602033

V. I. Yudin, O. N. Prudnikov, A. V. Taichenachev, M. Yu. Basalaev, V. G. Pal’chikov, S. N. Bagayev

引用次数: 0

Photothermal Conversion and Laser-Induced Transformations in Silicon–Germanium Alloy Nanoparticles 硅锗合金纳米粒子中的光热转换和激光诱导转变

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-11 DOI: 10.1134/S0021364024601398

S. O. Gurbatov, A. V. Shevlyagin, A. Yu. Zhizhchenko, E. B. Modin, A. A. Kuchmizhak, S. I. Kudryashov

{"title":"Photothermal Conversion and Laser-Induced Transformations in Silicon–Germanium Alloy Nanoparticles","authors":"S. O. Gurbatov, A. V. Shevlyagin, A. Yu. Zhizhchenko, E. B. Modin, A. A. Kuchmizhak, S. I. Kudryashov","doi":"10.1134/S0021364024601398","DOIUrl":"10.1134/S0021364024601398","url":null,"abstract":"Si1 – xGex alloy nanoparticles with controlled composition have been obtained by nanosecond laser ablation of silicon–germanium targets in isopropanol. The synthesized product exhibits a polycrystalline structure and a unimodal size distribution with a predominant content of microparticles and retains the stoichiometry of the composition of the targets used for the synthesis. Nanothermometry with the detection and analysis of a Raman signal from single alloy nanoparticles with a size of ~200 nm demonstrates a threefold increase (in comparison with nanoparticles of pure silicon) in the heating efficiency of a nanomaterial with the composition Si0.45Ge0.55 by 785-nm laser radiation falling into the first “transparency window” of biological tissues. Stimulated by continuous infrared radiation, the diffusion of silicon atoms to the surface (when heated to 650 K) and their oxidation lead to the gradual transformation of alloy nanoparticles into germanium clusters encapsulated in a SiOx matrix.","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"119 12","pages":"910 - 916"},"PeriodicalIF":1.4,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945213","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

Superconducting States in Metals with Toroidal Ordering 环状有序金属中的超导状态

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-11 DOI: 10.1134/S0021364024602689

V. P. Mineev

引用次数: 0

Disorder-Induced Singularity of the Quantum Metric 量子公设的无序奇异性

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-11 DOI: 10.1134/S0021364024601532

Z. Z. Alisultanov

引用次数: 0

Synthesis and Properties of a 12442-Family Superconductor 12442 层超导体的合成与特性

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-11 DOI: 10.1134/S0021364024602021

I. V. Zhuvagin, V. A. Vlasenko, A. S. Usoltsev, A. A. Gippius, K. S. Pervakov, A. R. Prishchepa, V. A. Prudkoglyad, S. Yu. Gavrilkin, A. D. Denishchenko, A. V. Sadakov

引用次数: 0

Origin of Optical Gain in Narrow ZnO Microrods with Whispering Gallery Modes 具有悄声画廊模式的窄 ZnO 微镜中光增益的起源

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-11 DOI: 10.1134/S0021364024601519

A. P. Tarasov, L. A. Zadorozhnaya, V. M. Kanevsky

引用次数: 0

Sign-Alternating Deviation of a Single-Particle Current–Voltage Characteristic of a Dirty SIN Junction 脏 SIN 结的单粒子电流-电压特性的符号偏差

IF 1.4 4区物理与天体物理

JETP Letters Pub Date : 2024-08-11 DOI: 10.1134/S0021364024601490

V. Ya. Kirpichenkov, N. V. Kirpichenkova, E. R. Kulinichev

{"title":"Sign-Alternating Deviation of a Single-Particle Current–Voltage Characteristic of a Dirty SIN Junction","authors":"V. Ya. Kirpichenkov, N. V. Kirpichenkova, E. R. Kulinichev","doi":"10.1134/S0021364024601490","DOIUrl":"10.1134/S0021364024601490","url":null,"abstract":"A formula for the single-particle current–voltage characteristic (J(V,T,c,beta )) of “dirty” (with low concentrations of identical nonmagnetic impurities in the disordered insulator layer) SIN junctions (S is a superconductor, I is a disordered insulator, and N is a normal metal) has been obtained in the region of low temperatures and voltages 0 ≤ |eV| ( ll ) T ( ll ) Δ0, where e is the elementary charge, Δ0 is the superconducting gap in the S edge of a junction at the temperature T = 0, V is the voltage across the junction, c ( ll ) 1 is the dimensionless concentration of impurities in the I layer, β = (ε0 – μ)/Δ0 is the dimensionless deviation of the single-impurity electron energy level ε0 relevant for this problem (on identical impurities in the I layer) from the electron chemical potential μ of the junction. It has been shown that an anomalously large sign-alternating deviation of the single-particle current–voltage characteristic of the dirty SIN junction from the value calculated by the existing theoretical expression is observed in a certain limited region Ωd(c, β) on the (c, β) parameter plane in the presence of random narrow-band quantum jumpers in the disordered I layer. A numerical example has demonstrated that the relative deviation of the single-particle current–voltage characteristic at typical values of the parameters of the dirty SIN junction in the region Ωd(c, β) can reach several orders of magnitude, which ensures the possibility of the experimental observation of this effect. The conditions for the applicability of the considered model of the dirty SIN junction have been discussed and the scheme of the corresponding experiment has been proposed.","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"119 12","pages":"957 - 965"},"PeriodicalIF":1.4,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945220","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