Abstract
With Maxwell-Bloch equations how the superradiance can lead to amplification and gain at a frequency much larger than the pumping frequency has been shown. This remarkable effect has been examined in terms of a simpler model involving two coupled oscillators, with one of them parametrically driven. We show that this coupled-oscillator model has a hidden parity-time () symmetry for quantum amplification by superradiant emission of radiation (QASER); we thus bring symmetry to the realm of parametrically coupled resonators. Moreover, we find that the QASER gain arises from the broken--symmetry phase. We then quantize the simplified version of QASER using quantum Langevin equations. The quantum description enables us to understand how the system starts from quantum fluctuations.
- Received 15 April 2017
DOI:https://doi.org/10.1103/PhysRevA.96.013827
©2017 American Physical Society