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## Spectrum of Andreev bound states in Josepshon junctions with a ferromagnetic insulator

Journal of Magnetism and Magnetic Materials. 2012. Vol. 324. P. 3467-3470.

Ferromagnetic-insulator (FI) based Josephson junctions are promising candidates for a coherent superconducting quantum bit as well as a classical superconducting logic circuit. Recently the appearance of an intriguing atomic-scale 0-pi transition has been theoretically predicted. In order to uncover the mechanism of this phenomena, we numerically calculate the spectrum of Andreev bound states in a FI barrier by diagonalizing the Bogoliubov-de Gennes equation. We show that Andreev spectrum drastically depends on the parity of the FI-layer number L and accordingly the pi (0) state is always more stable than the 0 (pi) state if L is odd (even).

Vasenko A. S., Golubov A. A., Silkin V. M. et al., JETP Letters 2017 Vol. 105 No. 8 P. 489-490

We study the effect of the Fermi surface anisotropy (hexagonal warping) on the superconducting pair potential, induced in a three-dimensional topological insulator (TI) by proximity with an s-wave superconductor (S) in presence of a magnetic moment of a nearby ferromagnetic insulator (FI). In the previous studies similar problem was treated with a simplified Hamiltonian, describing ...

Added: April 7, 2017

Demenev A. A., Grishina Y. V., Larionov A. V. et al., Physical Review B: Condensed Matter and Materials Physics 2017 Vol. 96 No. 15 P. 155308-1-155308-10

We address polarization instability in a freely decaying polariton condensate created by 2-ps-long linearly polarized laser pulses in the upper sublevel of the lower-polariton (LP) branch in a GaAs-based microcavity with reduced symmetry. The generated linearly polarized condensate is found to lose its stability at excitation densities above the threshold value: it passes into the ...

Added: February 15, 2018

Bezuglyi E. V., Vasenko A. S., Shumeiko V. S. et al., Physical Review B: Condensed Matter and Materials Physics 2005 Vol. 72 No. 1 P. 014501-1-014501-12

We study nonequilibrium effects in current transport through voltage biased tunnel junction with long diffusive superconducting leads at low applied voltage eV << 2 Delta, and finite temperatures. Due to a small value of the Josephson frequency, the quasiparticle spectrum adiabatically follows the time evolution of the superconducting phase difference, which results in the formation ...

Added: November 29, 2017

Vasenko A.S., Ozaeta A., Kawabata S. et al., Journal of Superconductivity and Novel Magnetism 2013 Vol. 26 P. 1951-1956

The Andreev current and the subgap conductance in a superconductor/ insulator/ ferromagnet (SIF) structure in the presence of a small spin-splitting field show novel interesting features (A. Ozaeta et al., Phys. Rev. B 86, 060509(R), 2012). For example, the Andreev current at zero temperature can be enhanced by a spin-splitting field h, smaller than the ...

Added: September 28, 2015

Мальшуков А. Г., Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 100 P. 035301-1-035301-7

A nonstationary anomalous Hall current is calculated for a voltage biased Josephson junction, which is composed of two s-wave superconducting contacts deposited on the top of a three-dimensional topological insulator (TI). A homogeneous Zeeman field was assumed at the surface of the TI. The problem has been considered within the ballistic approximation and on the ...

Added: March 11, 2020

Mal'shukov A., Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 102 P. 134509-1-134509-5

The Zeeman interaction results in spontaneous current through a Josephson contact with a spin-orbit coupled
normal metal, even in the absence of any voltage, or phase bias. In the case of the Rashba spin-orbit coupling
of electrons in a two-dimensional (2D) electron gas this effect takes place for the Zeeman field which is parallel
to the 2D system ...

Added: January 20, 2021

E. V. Deviatov, O. O. Shvetsov, EPL 2018 Vol. 122 No. 2 P. 27004-p1-27004-p5

We experimentally investigate charge transport through the interface between a niobium superconductor and a three-dimensional WTe2 Weyl semimetal. In addition to classical Andreev reflection, we observe sharp non-periodic subgap resistance resonances. From an analysis of their positions, magnetic field and temperature dependences, we can interpret them as an analog of Tomasch oscillations for transport along ...

Added: December 1, 2020

Ozaeta A., Vasenko A.S., Hekking F. W. et al., Physical Review B: Condensed Matter and Materials Physics 2012 Vol. 86 P. 060509-1-060509-5

We investigate the subgap transport properties of a S-F-Ne structure. Here S (Ne) is a superconducting (normal) electrode, and F is either a ferromagnet or a normal wire in the presence of an exchange or a spin- splitting Zeeman field respectively. By solving the quasiclassical equations we first analyze the behavior of the subgap current, ...

Added: September 28, 2015

A.G. Mal'shukov, Physical Review B: Condensed Matter and Materials Physics 2018 Vol. 97 P. 064515-1-064515-7

It is shown that the spin-orbit and Zeeman interactions result in phase shifts of Andreev-reflected
holes propagating at the surface of a topological insulator, or in Rashba spin-orbit-coupled two
dimensional normal metals, which are in a contact with an s-wave superconductor. Due to interference
of holes reflected through different paths of Andreev interferometer the electric current through
external contacts ...

Added: February 6, 2019

Sasaki A., Ikegaya S., Habe T. et al., Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 101 No. 184501 P. 184501-1-184501-6

We study theoretically the Josephson effect between two two-band superconductors respecting time-reversal
symmetry, where we assume a spin-singlet s-wave pair potential in each conduction band. The superconducting
phase at the first band ϕ1 and that at the second band ϕ2 characterize a two-band superconducting state. We
consider a Josephson junction where an insulating barrier separates two such two-band ...

Added: October 8, 2020

Kawabata S., Tanaka Y., Golubov A. A. et al., Physica C: Superconductivity and its Applications 2011 Vol. 471 No. 21-22 P. 1199-1201

We show a perturbation theory of the Josephson transport through ferromagnetic insulators (FIs). Recently we have found that the appearance of the atomic scale 0-pi transition in such junctions based on numerical calculations. In order to explore the mechanism of this anomalous transition, we have analytically calculated the Josephson current using the tunneling Hamiltonian theory ...

Added: November 29, 2017

Gordeeva A. V., Pankratov A. L., N.G. Pugach et al., Scientific Reports 2020 Vol. 10 No. 21961 P. 1-10

The Cosmic Microwave Background (CMB) radiation is the only observable that allows studying the earliest stage of the Universe. Radioastronomy instruments for CMB investigation require low working temperatures around 100 mK to get the necessary sensitivity. On-chip electron cooling of receivers is a pathway for future space missions due to problems of dilution fridges at ...

Added: December 10, 2020

Arutyunov K., Lehtinen J. S., Beilstein Journal of Nanotechnology 2020 Vol. 11 P. 417-420

Chain of superconductor-insulator-superconductor junctions based on Al-AlOx-Al... lift-off fabricated nanostructures was measured at ultra-low temperatures. At zero magnetic field the low current bias dynamic resistance can reach values ~1011 W. The system has been proved to provide a decent quality current biasing circuit enabling observation of Coulomb blockade and Bloch oscillations in ultra-narrow Ti nanowires ...

Added: September 18, 2020

Averin D. V., Wang G., A.S. Vasenko, Physical Review B: Condensed Matter and Materials Physics 2020 Vol. 102 No. 14 P. 144516-1-144516-6

We extend the basic theory of Andreev reflection (AR) in a normal metal/superconductor junction to the situation with an arbitrary time-dependent bias voltage V(t) across the junction. The central element of the theory is the fact that the Fourier transform of the AR amplitude has a casual structure. As an example, the theory is used to describe ...

Added: October 13, 2020

Averin D. V., Wang G., Vasenko A.S., / Cornell University. Series cond-mat "arxiv.org". 2020. No. 2007.07483.

We extend the basic theory of Andreev reflection (AR) in a normal metal/superconductor junction to the situation with an arbitrary time-dependent bias voltage V(t) across the junction. The central element of the theory is the fact that the Fourier transform of the AR amplitude has a casual structure. As an example, the theory is used to describe ...

Added: July 28, 2020

Klapwijk T. M., Ryabchun S., Journal of Experimental and Theoretical Physics 2014 Vol. 119 No. 6 P. 997-1017

An overview is presented of experiments on ballistic electrical transport in inhomogeneous super
conducting systems which are controlled by the process of Andreev reflection. The initial experiments based
on the coexistence of a normal phase and a superconducting phase in the intermediate state led to the concept
itself. It was followed by a focus on geometrically inhomogeneous systems ...

Added: March 27, 2015

Andrew G. Semenov, Zaikin A., Kuzmin L., Physical Review B: Condensed Matter and Materials Physics 2012 Vol. 86 No. 14 P. 144529-1-144529-5

We argue that electron-electron interactions fundamentally restrict the penetration length of Cooper pairs into a diffusive normal metal from a superconductor. At low temperatures, this Cooper pair dephasing length remains finite and does not diverge. We evaluate the subgap conductance of hybrids in the presence of electron-electron interactions and demonstrate that this length Lϕ can ...

Added: February 9, 2015

Vasenko A. S., Golubov A. A., Kupriyanov M. Y. et al., Physical Review B: Condensed Matter and Materials Physics 2008 Vol. 77 No. 13 P. 134507-1-134507-9

We investigate superconductor/insulator/ferromagnet/superconductor tunnel Josephson junctions in the dirty limit using the quasiclassical theory. We formulate a quantitative model describing the oscillations of critical current as a function of thickness of the ferromagnetic layer and use this model to fit recent experimental data. We also calculate quantitatively the density of states (DOS) in this type ...

Added: November 29, 2017

Antipov A., Seleznev V., Vakhtomin Y. et al., IOP Conference Series: Materials Science and Engineering (MSE) 2020 Vol. 781 No. 1 P. 012011-1-012011-5

Spectral characteristics of WSi and NbN superconducting single-photon detectors with different surface resistance and width of nanowire strips have been investigated in the wavelength range of 1.3-2.5 µm. WSi structures with narrower strips demonstrated better performance for detection of single photons in longer wavelength range. The difference in normalized photon count rate for such structures ...

Added: December 10, 2020

Budkov Y., Kolesnikov A. L., Polymer Science - Series C 2018 Vol. 60 No. Supplement 1 P. 148-159

Theoretical models of the conformational behavior of flexible polymer chains in mixed solvents enunciated in the world literature during the last decade are critically reviewed. Models describing different mechanisms of coil-to-globule transitions in a good solvent induced by cosolvent addition are highlighted. Special attention is given to the analysis of theoretical approaches to describing the ...

Added: November 30, 2018

Kalmykov A., Melentiev P., Balykin V., Laser Physics Letters 2020 Vol. 17 No. 4 P. 045901

In this paper we present measurements and comparison of SPP propagation length at the practically important telecom wavelength (1560 nm) as well as in the near-infrared and visible spectral ranges. The measurements were carried out for plane SPP waves excited on Ag film surface using optical microscopy of SPP waves in the far field. We ...

Added: January 15, 2021

Boldyrev K., Романов А., Хаула Е. et al., Journal of the American Ceramic Society 2019 Vol. 102 No. 5 P. 2745-2751

Single crystal of TlCl was doped with NIR photoluminescent univalent bismuth cations by prolonged immersion in liquid bismuth metal. The ion exchange Tl+ + Bi0 ↔ Tl0 + Bi+ at the crystal surface with subsequent Bi+ migration to the bulk are expected to drive the doping process. Contrary with Bi‐doped TlCl crystals, grown by Bridgman method, the ion exchange does ...

Added: February 8, 2019

M. : Faculty of Physics, MSU, 2017

The Low Temperature Physics Conference is an international event held every three years, under the auspices of the IUPAP through its Commission C5 on Low Temperature Physics. The aim of these conferences is to exchange information and views among the members of the international scientific community in the general field of Low Temperature Physics. It ...

Added: October 1, 2017

М. : National Instruments Russia, 2017

Содержание сборника составляют доклады с результатами оригинальных исследований и технических решений, ранее не публиковавшиеся. Мы надеемся, что предлагаемый сборник окажется полезным для специалистов, работающих в различных областях науки и техники, для широкого круга преподавателей, аспирантов и студентов ВУЗов, а также для преподавателей средних школ и технических колледжей. ...

Added: May 10, 2017