Lasing and transport in a quantum-dot resonator circuit

Abstract

We study a double quantum-dot system coherently coupled to an electromagnetic resonator. A current through the dot system can create a population inversion in the dot levels and, within a narrow resonance window, a lasing state in the resonator. The lasing state correlates with the transport properties. On one hand, this allows probing the lasing state via a current measurement. On the other hand, the resulting narrow current peak allows resolving small differences in the dot properties (e.g., a small difference in the Zeeman splittings of the two dots). For realistic situations relaxation processes have pronounced consequences. Remarkably, they may even enhance the resolution between differ..