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Time-dependent Andreev reflection
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 the current response to short pulses of the bias voltage, which create coherent superposition of quasiparticle states with different energies. The current oscillates in time, with the gap frequency Δ/ℏ, and also as a function of the pulse area ∫V(t)dt, with the period of the single-electron flux quantum e/h.
Keywords: Andreev reflectionандреевское отражениеmesoscopic superconductivityмезоскопическая сверхпроводимость
Publication based on the results of:
Arutyunov K., M. : Lebedev Institute, 2017
Superconducting properties of metallic nanowires can be entirely different from those of bulk superconductors because of the dominating role played by thermal and quantum fluctuations of the order parameter. For superconducting channels with diameters below ∼ 50 nm fluctuations of the phase of the complex order parameter - the phase slippage - lead to non-zero ...
Added: October 1, 2017
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
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
Temu E., Lahteenmaki P., Golubev D. et al., Journal of Low Temperature Physics 2017 Vol. 189 P. 204-216
We have employed noise thermometry for investigations of thermal relaxation
between the electrons and the substrate in nanowires patterned from 40-nm-thick
titanium film on top of silicon wafers covered by a native oxide. By controlling the
electronic temperature Te by Joule heating at the base temperature of a dilution refrigerator,
we probe the electron–phonon coupling and the thermal boundary ...
Added: December 5, 2017
Shein K., Zarudneva A., Emel’yanova V. et al., Physics of the Solid State 2020 Vol. 62 No. 9 P. 1539-1542
The transport properties of two types of quasi-one-dimensional superconducting microstructures were investigated at ultra-low temperatures: the narrow channels close-packed in the shape of meander, and the chains of tunneling contacts "superconductor-insulator-superconductor." Both types of the microstructures demonstrated high value of high-frequency impedance and-or the dynamic resistance. The study opens up potential for using of such ...
Added: September 18, 2020
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
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., Radkevich A. A. et al., Journal of Magnetism and Magnetic Materials 2018 Vol. 459 P. 356-358
Quasi-one-dimensional superconducting channels host sound-like plasma modes propagating along the
which are associated with fluctuations of the phase of the superconducting order parameter (Mooiji and
1985) [5]. Interaction between these electromagnetic excitations and charge carriers affects the electron density
of states (DOS). I-V characteristics of tunnel S1-I-S2 junctions, where superconducting S2 electrode
nanowire in the regime of quantum fluctuations ...
Added: October 1, 2017
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
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
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
K. Yu. Arutyunov, Lehtinen J. S., Radkevich A. A. et al., Physics of the Solid State 2017 Vol. 59 No. 11 P. 2110-2113
The current–voltage characteristics of superconductor–insulator–semiconductor (S1–I–S2)
tunnel junctions, where superconducting electrode S2 is a thin nanowire, are studied experimentally. The
observed blurring of the gap singularities is interpreted as a manifestation of the order parameter quantum
fluctuations. We propose a model taking into account the broadening of the density of states due to the interaction
of electrons with the ...
Added: November 29, 2017
Curran P., Kim J., Satchell N. et al., Applied Physics Letters 2015 Vol. 107 P. 262602-262602
We demonstrate that the magnetic state of a superconducting spin valve, that is normally controlled with an external magnetic field, can also be manipulated by varying the temperature which increases the functionality and flexibility of such structures as switching elements. In this case, switching is driven by changes in the magnetostatic energy due to spontaneous ...
Added: February 22, 2017
Denisov A., Bubis A., Piatrusha S. et al., Nanomaterials 2022 Vol. 12 No. 9 Article 1461
Mesoscopic superconductivity deals with various quasiparticle excitation modes, only one of them—the charge-mode—being directly accessible for conductance measurements due to the imbalance in populations of quasi-electron and quasihole excitation branches. Other modes carrying heat or even spin, valley etc. currents populate the branches equally and are charge-neutral, which makes them much harder to control. This ...
Added: April 3, 2023
Arutyunov K., Lehtinen J. S., Радкевич А. А. et al., Физика твердого тела 2017 Т. 59 № 11 С. 2092-2094
The current–voltage characteristics of superconductor–insulator–semiconductor (S1–I–S2)
tunnel junctions, where superconducting electrode S2 is a thin nanowire, are studied experimentally. The
observed blurring of the gap singularities is interpreted as a manifestation of the order parameter quantum
fluctuations. We propose a model taking into account the broadening of the density of states due to the interaction
of electrons with the ...
Added: October 1, 2017
Shapiro D., Mirlin A., Shnirman A., Physical Review B: Condensed Matter and Materials Physics 2021 Vol. 104 No. 3 Article 035434
We consider an interferometer based on artificially induced topological superconductivity and chiral one-dimensional (1D) Majorana fermions. The (nontopological) superconducting island inducing the superconducting correlations in the topological substrate is assumed to be floating. This allows probing the physics of interfering Majorana modes via microwave response, i.e., the frequency-dependent impedance between the island and the earth. ...
Added: October 31, 2021
Arutyunov K., Уфа : Уфа: НИЦ «Аэтерна», 2020, 2020
Quantum fluctuations of the order parameter in quasi-1D-superconductors ...
Added: January 25, 2021
Ioselevich P., Chuklanov D. A., JETP Letters 2021 Vol. 113 P. 631-637
We consider a long diffusive Josephson junction where the weak link is a thin (normal metal (N)–ferromagnet (F)) bilayer (N and F form parallel links between superconductors (Ss)). We show that superconductivity in the weak link can be described by an effective one-dimensional Usadel equation containing a “diluted” exchange field as well as a weak ...
Added: October 25, 2021
Stroganov P. L., Ya. V. Fominov, / Cornell University. Series cond-mat "arxiv.org". 2017. No. arXiv:1708.05089.
We consider ballistic SQUIDs with spin filtering inside half-metallic ferromagnetic arms. A singlet Cooper pair cannot pass through an arm in this case, so the Josephson current is entirely due to the Cooper pair splitting, with two electrons going to different interferometer arms. In order to elucidate the mechanisms of Josephson transport due to split ...
Added: October 18, 2017
Dolgoprudni : [б.и.], 2016
Book of abstracts ...
Added: November 20, 2016
Radkevich A., Semenov A. G., Zaikin A., European Physical Journal: Special Topics 2019 Vol. 227 No. 15-16 P. 2289-2295
We investigate the influence of quantum phase fluctuations on electron density of states (DOS) in ultrathin superconducting films and nanowires. Using an effective action approach we derive a non-perturbative correction to DOS in such systems. The main effect of phase fluctuations in quasi-two-dimensional films is the appearance of electron states at subgap energies while in ...
Added: October 28, 2019
Kawabata S., Tanaka Y., Golubov A. A. et al., 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 ...
Added: September 28, 2015
Андрияхина Е. С., Burmistrov I., Журнал экспериментальной и теоретической физики 2022 Т. 162 № 4 С. 522-540
The interplay of Anderson localization and electron-electron interactions is known to lead to enhancement of superconductivity due to multifractality of electron wave functions. We develop the theory of multifractally-enhanced superconducting states in two-dimensional systems in the presence of spin-orbit coupling. Using the Finkel'stein nonlinear sigma model, we derive the modified Usadel and gap equations that ...
Added: November 13, 2022
П.А.Иоселевич, Чукланов Д. А., Письма в Журнал экспериментальной и теоретической физики 2021 Т. 113 № 10 С. 661-668
Рассматривается длинный диффузный контакт Джозефсона, слабой связью в котором является тонкий бислой нормальный металл (N)–ферромагнетик (F), так что N и F образуют параллельные связи между сверхпроводниками S. Показано, что сверхпроводимость в такой слабой связи описывается эффективным одномерным уравнением Узаделя, содержащим ослабленное обменное поле, а также распаривающий член. Механизм распаривания основан на неотъемлемой неоднородности бислоя и ...
Added: October 25, 2021