nl0c02166_si_001.pdf (1.14 MB)
On-Demand Optical Generation of Single Flux Quanta
journal contribution
posted on 2020-08-06, 22:21 authored by Antonine Rochet, Vasiliy Vadimov, William Magrini, Siddharatha Thakur, Jean-Baptiste Trebbia, Alexander Melnikov, Alexander Buzdin, Philippe Tamarat, Brahim LounisSuperconductors
can host quantized magnetic flux tubes surrounded
by supercurrents, called Abrikosov vortices. Vortex penetration into
a superconducting film is usually limited to its edges and triggered
by external magnetic fields or local electrical currents. With a view
to novel research directions in quantum computation, the possibility
to generate and control single flux quanta in situ is thus challenging.
We introduce a far-field optical method to sculpt the magnetic flux
or generate permanent single vortices at any desired position in a
superconductor. It is based on a fast quench following the absorption
of a tightly focused laser pulse that locally heats the superconductor
above its critical temperature. We achieve ex-nihilo creation of a
single vortex pinned at the center of the hotspot, while its counterpart
opposite flux is trapped tens of micrometers away at its boundaries.
Our method paves the way to optical operation of Josephson transport
with single flux quanta.