Microwave generation and vortex jets in superconductor nanotubes

Autor(en)

Igor Bogush, Oleksandr V. Dobrovolskiy, Vladimir M. Fomin

Abstrakt

The dynamics of magnetic flux quanta (Abrikosov vortices) determine the resistive response of superconductors. In pinning-free planar thin films, the penetration and motion of vortices are controlled by edge defects, leading to such arrangements as vortex chains, vortex jets, and phase-slip regimes. Here, relying upon the time-dependent Ginzburg-Landau equation, we predict that these vortex patterns should appear in superconductor open nanotubes even without edge defects, due to the inhomogeneity of the normal magnetic induction component Bn, caused by the three-dimensional (3D) tube geometry. The crossing of the half tubes by dc-driven vortices induces GHz-frequency voltage U oscillations with spectra Uf(B) evolving between nf1 and nmf1 [f1: vortex nucleation frequency; n,m≥2] and blurred in certain ranges of currents and fields. An nf1 spectrum corresponds to a single vortex-chain regime typical for low B and for tubes of small radii. At higher fields, an nmf1 spectrum points to the presence of m vortex chains in the vortex jets which, in contrast to planar thin films, are not diverging because of constraint to the tube areas where Bn is close to maximum. A blurry spectrum implies complex arrangements of vortices because of multifurcations of their trajectories. Finally, due to a stronger confinement of single vortex chains in tubes of small radii, we reveal peaks in dU/dB and jumps in the frequency of microwave generation, which occur when the number of fluxons moving in the half tubes increases by one. In all, our findings are essential for novel 3D superconductor devices which can operate in few- and multifluxon regimes.

Organisation(en)

Nanomagnetismus und Magnonik

Externe Organisation(en)

Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden, Moldova State University

Journal

Physical Review B

Band

109

Anzahl der Seiten

12

ISSN

2469-9950

DOI

https://doi.org/10.1103/PhysRevB.109.104516

Publikationsdatum

03-2024

Peer-reviewed

Ja

ÖFOS 2012

103033 Supraleitung, 103017 Magnetismus

ASJC Scopus Sachgebiete

Electronic, Optical and Magnetic Materials, Condensed Matter Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/c550232c-f22e-4bd5-9093-12af75679e3f