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arXiv · cond-mat/0406014

Light Mediated Superconducting Transistor

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.

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A. V. Kavokin, I. A. Shelykh, M. M. Glazov. 2004-06-01. Light Mediated Superconducting Transistor. https://doi.org/10.1002/pssc.200460348

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