Conditions for experimental detection of one-way quantum steering in a three-mode optomechanical system

Conditions for experimental detection of asymmetric one-way quantum steering in a three-mode optomechanical system are examined. We consider cases of collective steering in which two modes collectively interact with the third mode, and the case of separate modes steering in which two mutually independent modes interact with the third mode. We find that the occurrence of both collective and separate modes quantum steering results not from an asymmetry between thermal noise of the modes, as it has been realized in linear optics systems, but from an asymmetry between the damping rates of the modes. We show the requirement that the modes are damped with different rates to be the necessary and sufficient condition for collective steering. In the case of separate modes, we find that apart from unequal damping rates, an additional condition is required that the modes are coupled to the third mode with unequal strengths. Thus, the generation of quantum steering between separate modes is more restrictive to the parameters than the collective steering. Determination of conditions for experimental detection of one-way steering in multi-mode system could give a new stimulus to develop secure directional communication networks.