Imaging the Anisotropic Nonlinear Meissner Effect in Nodal YBa${}_2$Cu${}_3$O${}_{7-\delta }$ Thin-Film Superconductors

Abstract

We have directly imaged the anisotropic nonlinear Meissner effect in an unconventional superconductor through the nonlinear electrodynamic response of both (bulk) gap nodes and (surface) Andreev bound states. A superconducting thin film is patterned into a compact self-resonant spiral structure, excited near resonance in the radio-frequency range, and scanned with a focused laser beam perturbation. At low temperatures, direction-dependent nonlinearities in the reactive and resistive properties of the resonator create photoresponse that maps out the directions of nodes, or of bound states associated with these nodes, on the Fermi surface of the superconductor. The method is demonstrated on the nodal superconductor YBa${}_2$Cu${}_3$O${}_{7-\delta }$ and the results are consistent with theoretical predictions for the bulk and surface contributions.

5 pages, 3 figures, Phys. Rev. Lett. (in press)

References in corpus (5)

• The Physics and Applications of Superconducting Metamaterials
• Unconventional superconductors under rotating magnetic field I: density of states and specific heat
• Unconventional rf photoresponse from a superconducting spiral resonator
• Strong surface contribution to the Nonlinear Meissner Effect
• Effect of LaAlO3 twin-domain topology on local dc and microwave properties of cuprate films

Cited by in corpus (3)

• Topological surface states in nodal superconductors
• Progress in Superconducting Metamaterials
• Topological flat bands in optical checkerboard-like lattices