Theory of noiseless phase-mixing amplification in a cavity   optomechanical system
  The investigation of the ultimate limits imposed by quantum mechanics on amplification represents an important topic both on a fundamental level and from the perspective of potential applications. We propose here a novel setup for an optomechanical amplifier, constituted by a mechanical resonator dispersively coupled to an optomechanical cavity asymmetrically driven around both mechanical sidebands. We show that, on general grounds, the present amplifier operates in a novel regime-- which we here call phase-mixing amplification. At the same time, for a suitable choice of parameters, the amplifier proposed here operates as a phase-sensitive amplifier. Furthermore, we show that both configurations allow amplification below the standard quantum limit in a parameter range compatible with current experiments in microwave circuit optomechanics. 
C. F. Ockeloen-Korppi, T. T. Heikkil\"a, M. A. Sillanp\"a\"a, F.   Massel
cond-mat.mes-hall physics.optics quant-ph