Linear response of open quantum systems

Linear response of open quantum systems

Many of the most important researches in modern quantum sciences and technologies, such as precise quantum measurements, quantum detection and sensing, quantum amplifiers, as well as the description of important phenomena such as electromagnetic induced transparency and Fano resonance, are directly related to the linear response of quantum systems to external stimuli. In this lecture, we show how an open quantum system that is in thermodynamic equilibrium with its surroundings at a certain temperature responds when it is affected by an external driving factor. Finally, we investigate the linear response of an optomechanical system to a weak time-dependent perturbation in the framework of the generalized linear response theory.