Photon Bose-Condensate as a Tunable Terahertz Laser Source without Inversion

Abstract

We develop a theoretical model for a tunable coherent terahertz radiation source based on the long-lived Bose condensate of photons. In the device we propose, the original photon pumping is performed incoherently by a blackbody radiation emitter. The photons thus produced Bose-condense by the inelastic relaxation on a two-dimensional electron gas in a perpendicular magnetostatic field. The process involves neither population inversion nor light wave amplification the standard laser sources are built on. The coherence and tunability of the light emitted by such a photon condensate are provided and supported by the discrete spectrum of the electron gas in the quantizing magnetic field. The device is a compact-size semiconductor crystal. We propose the design and perform the realistic calculations of the physical properties and limiting factors for the terahertz photon Bose-condensate resonator. We show that our terahertz source can deliver the highly coherent light emission in the frequency range of 3-30 THz for the magnetic field induction of the order of 2 T, with the upper emission frequency limit adjustable by the strength of the magnetic field applied.

The results of this article have been totally reconsidered and require too many corrections to be implemented to be publishable