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Scalable nanocomposite parylene-based memrist.rs:Multifilamentary resist.ve switching and neuromorphic applications

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Nano Research 2023年第2期16卷 3207-3214页

作者： Anna N.Matsukatova Artem Yu.Vdovichenko Timofey D.Patsaev Pavel A.Forsh Pavel K.Kashkarov Vyacheslav A.Demin Andrey V.Emelyanov National Research Centre“Kurchatov institute” Moscow 123182Russia physics.Department Lomonosov Moscow State UniversityMoscow 119991Russia Moscow institute of physics.and Technology DolgoprudnyjMoscow oblast 141701Russia Enikolopov institute of Synthetic Polymeric Materials Russian Academy of SciencesMoscow 117993Russia physics.Department Saint Petersburg State UniversitySt.Petersburg 199034Russia

Memrist.rs are promising candidates for synapse emulation in brain-inspired neuromorphic computing *** main obst.cle to their usage in such syst.ms is high variability of memrist.ve characterist.cs and its severe negative effect on the neural network *** paper addresses the issue from two points of view on the example of the parylene-based memrist.rs:(i)the methods of the memrist.r internal st.chast.city decrease and(ii)the methods of the memrist.ve neural network architecture *** introduction of an optimal Ag nanoparticle concentration(3 vol.%–6 vol.%)to the memrist.ve st.ucture leads to a st.tist.cally significant decrease in the switching voltage variation and endurance ***,it is shown that post.fabrication annealing improves memrist.ve characterist.cs,e.g.,resist.ve switching window increases by an order of magnitude and exceeds 106,the switching voltage variation decreases by a factor of 2(down to 7%for the set and 17%for the reset voltage),and thermost.bility is *** transmission electron microscopy and impedance spectroscopy analysis allowed est.blishing a multifilamentary resist.ve switching mechanism for nanocomposite parylene-based *** simulation of the formal neural network based on these memrist.rs demonst.ates high classification accuracy with low variation for an important biomedical task,heart disease prediction,after careful feature selection and network architecture *** prospects of the controlled incorporation of the nanocomposite parylene-based memrist.rs in neural networks are brightened by their scaling possibility in crossbar geometry.

关键词： memrist.r resist.ve switching neuromorphic computing parylene nanocomposite

Coulomb Interaction between Electrons and a New Concept of Atom

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Journal of Modern physics 2022年第4期13卷 495-508页

作者： Marina V. Krasinkova ioffe institute Politekhnicheskaya 26 St. Petersburg Russia

It is shown that the approximation of a st.ong Coulomb interaction between electrons results in a new model of the atom with a spatial quantization of electrons accompanied by their quantization in energy. This model implies that electrons rotate in circular orbits centered outside the atomic nucleus and only orbit axes pass through it. The Coulomb interaction between electrons leads to a spherically symmetric dist.ibution of their orbits on the surfaces of equipotential spheres of a spherically symmetric electrost.tic field of the nucleus. The dist.ibution is similar to “inscribing” electron orbits into faces of regular nucleus-centered polyhedra so each polyhedron corresponds to a certain electron st.te (s, p, d, f), and a certain set of polyhedra corresponds to a certain period of the Mendeleev Table. It is shown that a spherically symmetric dist.ibution of electron orbits gives rise to the formation of electron pairs in which electron orbits with a common axis are located symmetrically with respect to the nucleus and the orbital magnetic moments of the electrons are oppositely directed. The physical meaning of the electron spin concept becomes clear. The spin turns out to be related to the orbital magnetic moment of an electron and reflects the fact that two electrons of a pair rotate in opposite directions relative to their common axis. So the spin is one of characterist.cs of the electron st.te in the atom associated with electron rotation in the orbit centered outside the nucleus. The atomic model gives an insight into the periodicity of changes in the atomic properties with increasing nuclear charge and the reasons for an electron double energy quantization associated with different st.tes and periods. The model shows that the atomic st.ucture and properties can be explained by using concepts of classical mechanics and classical electrodynamics which regard the electron as a particle.

关键词： Correlated Electron st.te Electron Shell st.ucture Electron Energy Quantization Electron Pairing Electron Spin Magnetic Dipole-Dipole Interaction Closed Syst.m

Meteorite Chelyabinsk: Features of Dest.uction

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Natural Science 2018年第11期10卷 430-435页

作者： Olga G. Gladysheva Ast.ophysical Department of ioffe institute St. Petersburg Russia

A space object exploded near the city of Chelyabinsk on February 15, 2013. Meteorite fragments reached the Earth’s surface, and accordingly we may consider this space object to have been a meteorite. However, this event showed a number of features not corresponding to the dest.uction of a meteorite. The space object began to disintegrate at an altitude of 70 km when pressure (dynamical loads) on its front surface was ~6.7 × 103 N·m-2. The subst.nce from the object’s surface was not blown off by drops, as at ablation, but was dumped by jets over a dist.nce up to 1 km. The trail of this space object visually reminded us of a jet aircraft’s contrail, made up of water. But there is no enough water at altitudes of 30 - 70 km. It may be assumed that the object itself delivered water to these altitudes. The calculation of gas rise over the trail showed that the temperature in some parts of this trail was about 900 K. Heating of large masses of gas can be explained not only by the release of kinetic energy of the space object, but also by combust.on processes of its subst.nce. Thus, it was concluded that the meteorite could have been delivered by a comet.

关键词： Meteorites Comets Atmospheric Effects

Long-Term Trends of Carbon Monoxide Total Columnar Amount in Urban Areas and Background Regions:Ground-and Satellite-based Spectroscopic Measurements

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Advances in Atmospheric Sciences 2018年第7期35卷 785-795页

作者： Pucai WANG N.F.ELANSKY Yu.M.TIMOFEEV Gengchen WANG G.S.GOLITSYN M.V.MAKAROVA V.S.RAKITIN Yu.SHTABKIN A.I.SKOROKHOD E.I.GRECHKO E.V.FOKEEVA A.N.SAFRONOV Liang RAN Ting WANG LAGEO Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China A.M.Obukhov institute of Atmospheric physics Russian Academy of SciencesMoscow 119017Russia st.petersburg.st.te University Saint-Petersburg 198904Russia

A comparative st.dy was carried out to explore carbon monoxide total columnar amount（CO TC） in background and polluted atmosphere, including the st.tions of ZSS（Zvenigorod）, ZOTTO（Central Siberia）, Peterhof, Beijing, and Moscow,during 1998–2014, on the basis of ground-and satellite-based spectroscopic measurements. Interannual variations of CO TC in different regions of Eurasia were obtained from ground-based spectroscopic observations, combined with satellite data from the sensors MOPITT（2001–14）, AIRS（2003–14）, and IASI Met Op-A（2010–13）. A decreasing trend in CO TC（1998–2014） was found at the urban site of Beijing, where CO TC decreased by 1.14% ± 0.87% yr^（-1）. Meanwhile, at the Moscow site, CO TC decreased remarkably by 3.73% ± 0.39% yr^（-1）. In the background regions（ZSS, ZOTTO, Peterhof）, the reduction was 0.9%–1.7% yr^（-1） during the same period. Based on the AIRSv6 satellite data for the period 2003–14, a slight decrease（0.4%–0.6% yr^（-1）） of CO TC was detected over the midlatitudes of Eurasia, while a reduction of 0.9%–1.2% yr^（-1） was found in Southeast.Asia. The degree of correlation between the CO TC derived from satellite products（MOPITTv6 Joint, AIRSv6 and IASI Met Op-A） and ground-based measurements was calculated, revealing significant correlation in unpolluted *** in polluted areas, IASI Met Op-A and AIRSv6 data underest.mated CO TC by a factor of 1.5–2.8. On average, the correlation coefficient between ground-and satellite-based data increased significantly for cases with PBL heights greater than 500 m.

关键词： carbon monoxide trend spectroscopic measurement MOPITT AIRS IASI

Scaling behavior of the thermopower of the archetypal heavy-fermion metal YbRh2Si2

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Frontiers of physics 2016年第2期11卷 89-95页

作者： V. R. Shaginyan A. Z. Msezane G. S. Japaridze K. G. Popov J. W. Clark V. A. Khodel petersburg.Nuclear physics.institute NRC Kurchatov Institute Gatchina 188300 Russia Clark Atlanta University Atlanta GA 30314 USA Komi Science Center Ural Division RAS Syktyvkar 167982 Russia Department of physics St. Petersburg State University Russia McDonnell Center for the Space Sciences 8J Department of physics Washington University St. Louis MO 63130 USA Centro de Ciencias Matemdticas Universidade de Madeira 9000-390 Funchal Madeira Portugal russian Research Center Kurchatov institute Moscow 123182 Russia

We reveal and explain the scaling behavior of the thermopower S/T exhibited by the archetypal heavy-fermion （HF） metal YbRh2Si2 under the application of magnetic field B at temperature T. We show that the same scaling is demonst.ated by different HF compounds such as/3-YbA1B4 and the st.ongly correlated layered cobalt oxide [BiBa0.66K0.3602]CoO2. Using YbRh2Si2 as an example, we demonst.ate that the scaling behavior of SIT is violated at the antiferromagnetic phase transition, while both the residual resist.vity Po and the density of st.tes, N, experience jumps at the phase transition, causing the thermopower to make two jumps and change its sign. Our elucidation is based on flattening of the single-particle spectrum that profoundly affects Po and N. To depict the main features of the SIT behavior, we const.uct a T-B schematic phase diagram of YbRh2Si2. Our calculated SIT for the HF compounds are in good agreement with experimental facts and support our observations.

关键词： thermoelectric and thermomagnetic effects quantum phase transition flat bands,non-Fermi-liquid st.tes st.ongly correlated electron syst.ms heavy fermions

Influence of vanadium doping on the behavior of YBa_2Cu_3O_7-y

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Chinese Journal of Chemist.y 1994年第5期12卷 419-424页

作者： MENG, Jian REN, Yu-Fang LI, Xiao-GuangLaboratory of Rare Earth Chemist.y and physics. Changchun institute of Applied Chemist.y, Chinese Academy of Sciences, Changchun, Jilin 130022, ChinaPopov, V.V. Repin, S.M. Smirnov, LA. loffe Physicotechnical institute, russian Academy of Sciences, Saint petersburg. russia Laboratory of Rare Earth Chemist.y and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China ioffe Physicotechnical institute Russian Academy of Sciences Saint Petersburg Russia

YBa2Cu3-xVxO7-y(x=0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) superconductors have been prepared. X-ray diffraction shows that the syst.m remains orthorhombic for all compositions st.died, but for x > 0.4 V2O5 was detected as an impurity phase. Subst.tution of V5+ for Cu2+ occurs in the Cu(2) sites on the Cu(2)-O planes. The introduction of the high valence element, vanadium, produces the extra free-electrons. These electrons recombine with the positive carrier of the syst.m. It makes depression of the mobility and the Hall number of YBa2Cu3-xVxO7-v and also results in a depression of TC.

关键词： YBa2Cu3O7-y high-Tc superconductor vanadium doping impurity effect.

Quantum Conductance st.ircase of Edge Hole Channels in Silicon Quantum Wells

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Journal of Modern physics 2012年第11期3卷 1771-1775页

作者： Nikolay T. Bagraev Leonid E. Klyachkin Andrei A. Kudryavtsev Anna M. Malyarenko ioffe Physical Technical institute St. Petersburg Russia

We present the findings for the quantum conductance st.ircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with boron on the n-type Si (100) surface. This longitudinal quantum conductance st.ircase, Gxx, is revealed by the voltage applied to the Hall contacts, Vxy, to a maximum of 4e2/h. In addition to the st.ndard plateau, 2e2/h, the variations of the Vxy voltage appear to exhibit the fractional forms of the quantum conductance st.ircase with the plateaus and st.ps that bring into correlation respectively with the odd and even fractional values.

关键词： Quantum Conductance st.ircase Edge Channels Silicon Nanosandwich Odd and Even Fractional Values

Direct modulation characterist.cs of microdisk lasers with InGaAs/GaAs quantum well-dots

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Photonics Research 2019年第6期7卷 664-668页

作者： N.V.KRYZHANOVSKAYA E.I.MOISEEV F.I.ZUBOV A.M.MOZHAROV M.V.MAXIMOV N.A.KALYUZHNYY S.A.MINTAIROV M.M.KULAGINA S.A.BLOKHIN K.E.KUDRYAVTSEV A.N.YABLONSKIY S.V.MOROZOV YU.BERDNIKOV S.ROUVIMOV A.E.ZHUKOV st.petersburg.Academic University Khlopina 8/3 S t Petersburg 194021 Russia ioffe institute of RAS Politehnicheskaya 26 St. Petersburg 194021 Russia institute for physics.of Microst.ctures of RAS Nizhny Novgorod 603950 Russia ITMO University Kronverkskiy prospekt 49 St. Petersburg 197101 Russia University of Notre Dame Notre Dame Indiana 46556 USA

GaAs-based microdisk lasers with an active region representing a dense array of indium-rich islands(InGaAs quantum well-dots) were st.died using direct small-signal modulation. We demonst.ate that using dense arrays of InGaAs quantum well-dots enables uncooled high-frequency applications with a GHz-range bandwidth for microdisk lasers. A maximum 3 dB modulation frequency of 5.9 GHz was found in the microdisk with a radius of 13.5 μm operating without a heatsink for cooling. A modulation current efficiency factor of 1.5 GHz∕mA1∕2 was est.mated.

关键词： Direct modulation characterist.cs quantum well-dots

Nonlinear polaritons in a monolayer semiconductor coupled to optical bound st.tes in the continuum

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Light(Science & Applications) 2020年第1期9卷 1480-1487页

作者： Vasily Kravtsov Ekaterina Khest.nova Fedor A.Benimetskiy Tatiana Ivanova Anton K.Samusev Ivan S.Sinev Dmitry Pidgayko Alexey M.Mozharov Ivan S.Mukhin Maksim S.Lozhkin Yuri V.Kapitonov Andrey S.Brichkin Vladimir D.Kulakovskii Ivan A.Shelykh Alexander I.Tartakovskii Paul M.Walker Maurice S.Skolnick Dmitry N.Krizhanovskii Ivan V.Iorsh ITMO University Saint Petersburg 197101Russia st.petersburg.Academic University Saint Petersburg 194021Russia Saint petersburg.st.te University ul.Ulyanovskaya 1Saint Petersburg 198504Russia institute of Solid st.te physics RASChernogolovka 142432Russia Science institute University of IcelandDunhagi 3IS-107ReykjavikIceland Department of physics.and Ast.onomy University of SheffieldSheffield S37RHUK

Optical bound st.tes in the continuum(BICs)provide a way to engineer very narrow resonances in photonic *** extended interaction time in these syst.ms is particularly promising for the enhancement of nonlinear optical processes and the development of the next generation of active optical ***,the achievable interaction st.ength is limited by the purely photonic character of optical ***,we mix the optical BIC in a photonic cryst.l slab with excitons in the atomically thin semiconductor MoSe_(2) to form nonlinear exciton-polaritons with a Rabi splitting of 27 meV,exhibiting large interaction-induced spectral *** asymptotic BIC-like suppression of polariton radiation into the far field toward the BIC wavevector,in combination with effective reduction of the excitonic disorder through motional narrowing,results in small polariton linewidths below 3 *** with a st.ongly wavevector-dependent Q-factor,this provides for the enhancement and control of polariton–polariton interactions and the resulting nonlinear optical effects,paving the way toward tuneable BIC-based polaritonic devices for sensing,lasing,and nonlinear optics.

关键词： polar nonlinear continuum