Title: On the theory of nonhomogeneous nonequilibrium superconductivity in 2D systems with massless fermions

Abstract

Here we analyze static and nonequilibrium superconducting properties of a 2D relativistic-like model system with local electron-electron interaction, Rashba spin-orbit interaction αR in presence of time-dependent in-plane magnetic field H(t). It is shown that similar to the 2D case with ordinary massive quasiparticle dispersion ε(k)~|k|² at large fields, such a system demonstrates a nonhomogeneous superconducting stripe phase with the order parameter Δ(r)=Δ(0)cos(2[μ_BB×r]n/$$\hbarυ_F$$) (B is the magnetic induction, υF is the Fermi velocity, n is the normal to the plane, μ_B is the Bohr magneton, and αR$$\ll$$υF) where the stripes are oriented along the B direction. In the considered system, the inter-stripe period L and the magnitude of the magnetic field B are related by a universal relation BL=$$\hbarυ_F$$/μ_B≃0.714∙10^-4 Tm. Contrary to the case of massive quasiparticles, where the condition α_R~υ_F can be, in principle, satisfied by increasing α_R or by charge doping (Fermi velocity decreasing), in a relativistic-like system, where υF is doping-independent and one-two orders of magnitude larger than typical Fermi velocity in the “standard” 2D systems, the stripe phase can be the ground state at a rather low doping level. We also analyzed the nonequilibrium properties of the system with a focus on the melting of the stripe order (when the magnetic field is quenched to a lower value) and stripe dynamics (when the field is rotated by 90° degrees) and found several notable results. In particular, it was shown that the stripe domains melt according to law R~1$$\sqrt{t}$$ at initial times, while at longer times they shrink exponentially. In the case of the flipped magnetic field, the stripe orientation gradually turns from x- to y-direction, and the intermediate “crossed-stripe” phase takes place during times of order of picoseconds. Such a crossed phase is built of periodic superconducting bubbles that potentially may have applications in modern ultrafast superconducting technologies.

Authors:

Loktev, V. M. ^[1]; Turkowski, V. ^[2]

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+ Show Author Affiliations

1. National Academy of Science of Ukraine, Kiev (Ukraine); National Technical University of Ukraine, Kiev (Ukraine)
2. University of Central Florida, Orlando, FL (United States)

Publication Date:

Sun May 01 00:00:00 EDT 2022

Research Org.:

Univ. of Central Florida, Orlando, FL (United States)

Sponsoring Org.:

USDOE Office of Science (SC); National Academy of Sciences of Ukraine; Ministry of Education and Science of Ukraine (MESU); Ministry of Science and Technology of the State of Israel (MOST)

OSTI Identifier:

1978935

Grant/Contract Number:  

FG02-07ER46354; 0117U000236; 0117U000240

Resource Type:

Accepted Manuscript

Journal Name:

Low Temperature Physics

Additional Journal Information:

Journal Volume: 48; Journal Issue: 5; Journal ID: ISSN 1063-777X

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; superconductivity; superconductors; quasiparticle; electromagnetic induction; fundamental constants; spin-orbit interactions; graphene; quantum computing; bubble domains; Fermi-Dirac statistics