Causes and Consequences of Ordering and Dynamic Phases of Confined Vortex Rows in Superconducting Nanostripes

Abstract

Understanding the behaviour of vortices under nanoscale confinement in superconducting circuits is important for the development of superconducting electronics and quantum technologies. Using numerical simulations based on the Ginzburg–Landau theory for non-homogeneous superconductivity in the presence of magnetic fields, we detail how lateral confinement organises vortices in a long superconducting nanostripe, presenting a phase diagram of vortex configurations as a function of the stripe width and magnetic field. We discuss why the average vortex density is reduced and reveal that confinement influences vortex dynamics in the dissipative regime under sourced electrical current, mapping out transitions between asynchronous and synchronous vortex rows crossing the nanostripe as the current is varied. Synchronous crossings are of particular interest, since they cause single-mode modulations in the voltage drop along the stripe in a high (typically GHz to THz) frequency range.

Complex Phase-Fluctuation Effects Correlated with Granularity in Superconducting NbN Nanofilms

“…For a discussion of the resistive states associated with PS events in superconducting quasi-1D nanostructures, see ref. [ 51 ].…”

Hybrid Superconducting/Superconducting Mesoscopic Heterostructure Studied by Modified Ginzburg–Landau Equations

“…These developments have allowed new advances, including the superconducting proximity effect in epitaxial graphene induced by a graphene-superconductor interface [11]. Numerical calculations have shown many effects that are usually observed in nanostructured superconductors, and these result in complex vortex patterns when barriers or defects are included [12][13][14][15][16][17]. Additionally, the inclusion of anisotropies in superconducting samples through variations in T c in different layers of the sample leads to distinct vortex states and free-energy curves [18][19][20], as well as new possibilities for non-conventional vortex structures [21].…”

Novel Research in Low-Dimensional Systems

“…The search for novel self-assembled quantum dots with hole-localization energy that allow a long charge storage is very important to the field of non-volatile memory applications. The ninth paper by McNaughton et al [ 21 ] studies the causes and consequences of ordering and the dynamic phases of confined vortex rows in superconducting nanostripes. Superconducting nanostripes are a fundamental component in superconducting electronics, and they are crucial components for various applications in the field of quantum technology.…”