Light Mediated Superconducting Transistor

TL;DR

This paper proposes a novel light-mediated superconducting transistor utilizing BCS polariton condensation, enabling super-current flow at room temperature through stimulated scattering in an optical cavity.

Contribution

It introduces a new transistor concept based on BCS polariton superfluidity, combining light-matter coupling with superconducting-like behavior at high temperatures.

Findings

Phase diagram of electron-hole-polariton system calculated

Super-current can be induced and controlled via optical cavity coupling

Potential for room-temperature superconducting device implementation

Abstract

Bose-condensation of mass-less quasiparticles (photons) can be easily achieved at the room temperature in lasers. On the other hand, condensation of bosons having a non-zero mass requires usually ultra-low temperatures. Recently, it has been shown that polaritons, which are half-light-half-matter quasi-particles, may form condensed states at high temperatures (up to 300K). Polaritons composed by electron-hole pairs coupled to confined light modes in optical cavities may form a Bardeen-Cooper-Schriefer (BCS) superfluid. We propose a new transistor based on stimulated scattering of electron-hole pairs into the BCS polariton mode. A pn-junction embedded inside an optical cavity resonantly emits light into the cavity mode. If the cavity mode energy slightly exceeds the band-gap energy, it couples with electron-hole pairs with zero centre of mass wave-vector but non-zero wave-vector of relative motion. This creates a super-current in the plane of the structure. In an isotropic case, its direction is chosen by the system spontaneously. Otherwise, it is pinned to the external in-plane bias. We calculate the phase diagram for the electron-hole-polariton system.