Optical Manipulation of Single Flux Quanta

TL;DR

This paper presents a novel optical technique using focused laser heating to manipulate individual magnetic flux vortices in superconductors, enabling precise control for device applications and potential optical control of Josephson junctions.

Contribution

Introduces a simple, fast, and non-invasive optical method for single-vortex manipulation in superconductors, surpassing previous complex techniques.

Findings

Achieved precise control of individual Abrikosov vortices using focused laser heating.

Demonstrated potential for sculpting magnetic flux profiles in superconducting devices.

Paved the way for optical control of Josephson junctions with high parallelization.

Abstract

Magnetic field can penetrate into type-II superconductors in the form of Abrikosov vortices, which are magnetic flux tubes surrounded by circulating supercurrents often trapped at defects referred to as pinning sites. Although the average properties of the vortex matter can be tuned with magnetic fields, temperature or electric currents, handling of individual vortices remains challenging and has been demonstrated only with sophisticated magnetic force, superconducting quantum interference device or strain-induced scanning local probe microscopies. Here, we introduce a far-field optical method based on local heating of the superconductor with a focused laser beam to realize a fast, precise and non-invasive manipulation of individual Abrikosov vortices, in the same way as with optical tweezers. This simple approach provides the perfect basis for sculpting the magnetic flux profile in superconducting devices like a vortex lens or a vortex cleaner, without resorting to static pinning or ratchet effects. Since a single vortex can induce a Josephson phase shift, our method also paves the way to fast optical drive of Josephson junctions, with potential massive parallelization of operations.