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## Density of States of Narrow Superconducting Channels in the Regime of Quantum Fluctuations of the Order Parameter

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 Mooij–Schön plasmon mode emerging in a quasi-one-dimensional superconducting

channel in the regime of quantum fluctuations of the order parameter. The model gives results that

are in a reasonable qualitative agreement with the experimental data.

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

M. : Max press, 2016

The Book of Abstracts contains the abstracts of the papers presented at the biannual International
Conference “Micro- and Nanoelectronics – 2016” (ICMNE-2016) including the extended Session
“Quantum Informatics” (QI-2016). The Conference topics cover the most of the areas dedicated to
the physics of integrated micro- and nanoelectronic devices and related micro- and nanotechnologies.
The Conference is focused on recent ...

Added: February 26, 2017

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

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

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., Rantala T., Physical Review Letters 2014

The topic of quantum fluctuations in quasi-1D superconductors, also called quantum phase slips (QPS), has
attracted a significant attention. It has been shown that the phenomenon is capable to suppress zero resistivity of
ultra-narrow superconducting nanowires at low temperatures T<<Tc and quench persistent currents in tiny
nanorings. It has been predicted that a superconducting nanowire in the regime ...

Added: March 24, 2014

Arutyunov K., Lehtinen J. S., Nanoscale Research Letters 2016 Vol. 11 No. 364 P. 1-4

Tunneling I–V characteristics between very narrow titanium nanowires and “massive” superconducting
aluminum were measured. The clear trend was observed: the thinner the titanium electrode, the broader the
singularity at eV = Δ1(Al) + Δ2(Ti). The phenomenon can be explained by broadening of the gap edge of the
quasi-one-dimensional titanium channels due to quantum fluctuations of the order parameter ...

Added: November 19, 2016

Dolgoprudni : [б.и.], 2016

Book of abstracts ...

Added: November 20, 2016

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

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

Arutyunov K., Lehtinen J. S., Rantala T., Journal of Physics: Conference Series 2014

The topic of quantum fluctuations in quasi-1D superconductors, also called quantum phase slips (QPS), has attracted a significant attention. It has been shown that the phenomenon is capable to suppress zero resistivity of ultra-narrow superconducting nanowires at low temperatures T<<Tc and quench persistent currents in tiny nanorings. It has been predicted that a superconducting nanowire ...

Added: March 24, 2014

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

Arutyunov, K.Y., Astafiev O. V., Ioffe L. B. et al., Nature 2012 Vol. 484 No. 7394 P. 355-358

A hundred years after the discovery of superconductivity, one
fundamental prediction of the theory, coherent quantum phase
slip (CQPS), has not been observed. CQPS is a phenomenon exactly
dual1 to the Josephson effect; whereas the latter is a coherent
transfer of charges between superconducting leads2,3, the former
is a coherent transfer of vortices or fluxes across a superconducting
wire. In contrast ...

Added: March 24, 2014

Arutyunov K. Yu., Chernyaev S. A., Karabassov T. et al., Journal of Physics: Condensed Matter 2018 Vol. 30 No. 343001 P. 1-16

Rapid development of micro- and nanofabrication methods have provoked interest
and enabled experimental studies of electronic properties of a vast class of (sub)micrometersize
solid state systems. Mesoscopic-size hybrid structures, containing superconducting
elements, have become interesting objects for basic research studies and various applications,
ranging from medical and astrophysical sensors to quantum computing. One of the
most important aspects of physics, ...

Added: July 31, 2018

Arutyunov K., Lehtinen J. S., Zakharov K., Physical Review Letters 2012 Vol. 109 No. 18 P. 187001-187005

Quantum fluctuations in quasi-one-dimensional superconducting channels leading to spontaneous
changes of the phase of the order parameter by 2, alternatively called quantum phase slips (QPS),
manifest themselves as the finite resistance well below the critical temperature of thin superconducting
nanowires and the suppression of persistent currents in tiny superconducting nanorings. Here we report the
experimental evidence that in a ...

Added: March 24, 2014

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

Semenov A. G., Zaikin A., Physical Review B: Condensed Matter and Materials Physics 2019 Vol. 99 No. 9 P. 094516-1-094516-9

We work out a microscopic theory describing complete statistics of voltage fluctuations generated by quantum phase slips (QPS) in superconducting nanowires. We evaluate the cumulant generating function and demonstrate that shot noise of the voltage as well as the thir d and all higher voltage cumulants differ from zero only due to the presence of ...

Added: October 31, 2019

Aladyshkin A., Nefedov I. undefined., Aladyshkina A. S. et al., Physica C: Superconductivity and its Applications 2012 Vol. 479 P. 98-101

We investigate numerically the formation of vortex–antivortex pairs in thin-film superconducting strip in the presence of a straight current-carrying wire, oriented perpendicular to this strip. We demonstrate that the change in the number of the trapped vortices/antivortices inside the strip near the current-carrying wire results in a oscillatory dependence of the critical current Ic on ...

Added: November 19, 2012

Konstantin Yu. Arutyunov, Hongisto T. T., Lehtinen J. S. et al., Scientific Reports 2012 Vol. 2 No. 293 P. 1-7

The smaller the system, typically - the higher is the impact of fluctuations. In narrow superconducting wires
sufficiently close to the critical temperature Tc thermal fluctuations are responsible for the experimentally
observable finite resistance. Quite recently it became possible to fabricate sub-10 nm superconducting
structures, where the finite resistivity was reported within the whole range of experimentally obtainable
temperatures. ...

Added: March 24, 2014

Arutyunov K., Sajavaara T., Lehtinen J. S. et al., Physical Review B: Condensed Matter and Materials Physics 2012 Vol. 85 No. 9 P. 0945081-0945087

Electron transport properties of titanium nanowires were experimentally studied. Below the effective diameter
50nm all samples demonstrated a pronounced broadening of the R(T ) dependencies, which cannot be accounted
for by thermal fluctuations. Extensive microscopic and elemental analyses indicate the absence of structural or/and
geometrical imperfections capable of broadening the R(T ) transition to such an extent. We ...

Added: March 24, 2014

Moiseev E., Kryzhanovskaya N., Zhukov A. et al., Optics Letters 2018 Vol. 43 No. 19 P. 4554-4557

We study injection GaAs-based microdisk lasers capable of operating at room and elevated temperatures. A novel type of active region is used, namely InGaAs quantum well-dots representing a dense array of indium-rich islands formed inside an indium-depleted residual quantum well by metalorganic vapor phase epitaxy. We demonstrate a high output power of 18 mW, a differential ...

Added: September 27, 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

Korneev A., Дивочий А. В., Ватомин Ю. Б. et al., Журнал радиоэлектроники 2013 № 5 С. 2

Представлены недавние результаты в исследовании и разработке сверхпроводникового однофотонного детектора (superconducting single-photon detector, SSPD). Достигнут прогресс по следующим показателям: 1) созданы и охарактеризованы SSPD, интегрированные с оптическим резонатором и освещаемые с передней стороны, а не через подложку; 2) посредством уменьшения ширины полоски детектора до 40 нм увеличена квантовая эффективность на длинах волн в районе 3 ...

Added: March 16, 2015

Arutyunov K., Lehtinen J. S., Superconductor Science and Technology 2012 Vol. 25 P. 1240071-1240075

In a number of recent experiments it has been demonstrated that in ultra-narrow
superconducting channels quantum fluctuations of the order parameter, alternatively called
quantum phase slips, are responsible for the finite resistance well below the critical
temperature. Acceptable agreement between those experiments and the models describing
quantum fluctuations in quasi-one-dimensional superconductors has been established.
However, the very concept of phase ...

Added: March 24, 2014