Transport properties of Andreev polarons in superconductor-semiconductor-superconductor junction with superlattice structure

TL;DR

This study investigates the transport properties of superconductor-semiconductor-superconductor junctions with superlattice structures, revealing oscillatory differential resistance under RF irradiation and proposing the formation of Andreev polarons due to strong quasiparticle-phonon coupling.

Contribution

It introduces the concept of Andreev polarons formed by strong quasiparticle-phonon coupling in superlattice S-Sm-S junctions under RF irradiation.

Findings

Oscillatory differential resistance observed at 1.77 GHz RF frequency.

Experimental data explained by quasiparticle-phonon coupling model.

Proposal of Andreev polarons as new composite particles.

Abstract

Transport properties of a superconductor-semiconductor-superconductor (S-Sm-S) junction with superlattice structure are investigated. Differential resistance as a function of voltage shows oscillatory behavior under the irradiation of radio-frequency (RF) waves with the specific frequency of 1.77 GHz regardless of the superconducting materials and the junction lengths. Experimental data are quantitatively explained in terms of the coupling of superconducting quasiparticles with long-wavelength acoustic phonons indirectly excited by the RF waves. We propose that the strong coupling causes the formation of novel composite particles, Andreev polarons.