Optical Amplification And Fast-slow Light In A Three-mode Cavity Optomechanical System Without Rotating Wave Approximation

In recent years,information storage of light at different frequency modes has attracted wide attention,because of its key action in long-distance and high-speed quantum com-munication.With the development of science and technology,a variety of experimental devices for optical storage have been proposed and studied,including an important and recently popular device:cavity optomechanical system.Cavity optomechanic,which mainly studies the interaction between mechanical modes and optical modes and the related quantum effects,is an important research field recently and has attracted the atten-tion of many researchers,thus it has developed rapidly.By using cavity optomechanical system,it is possible to achieve a mechanical response of system controlled by one light field or,conversely,an optical response of system controlled by a mechanical model or another light field.This property of cavity optomechanical system makes it have potential applications in quantum optical effect,ultra-sensitive measurement and quantum infor-mation processing.Due to the nonlinear coupling between optical modes and mechanical modes,many different quantum effects can be realized in cavity optomechanical systems,such as quantum entanglement,cooling of mechanical modes,non-reciprocal transmis-sion,optomechanically induced transparency,optomechanically induced amplification,and so on.It is well known that the rotating wave approximation is a common means in the research of atomic motion to eliminating the perturbations.In the domain of cavity optomechanics,there has been a great deal of researches using the rotational wave ap-proximation method in the dynamical analysis of systems.Recently,some investigates have specifically analyzed the influence of perturbation term on the system.Inspired by this,our work mainly studies the influence of the rotating wave approximation method in the three-mode cavity optomechanical system.The details are as follows:Based on a cavity optomechanical system consisted of an optical cavity and two charged nanomechanical resonators,the effect of the counterrotating term on the system is studied.There are two absorption windows in the probe output spectrum as the Coulomb coupling between two charged nanomechanical resonators.When the rotating wave approximation method is not used in the dynamic analysis of the system,the minimum values of the two absorption windows in the absorption curve are greater than zero,which leads to the symmetrical double optomechanically induced transparency effect.By using the rotating wave approximation method in the dynamic analysis of the system,the minimum values of the two absorption windows in the absorption curve are less than zero,and the line shapes are asymmetric about the resonance point.It means that the asymmetric double optomechanically induced amplification effect appears in the system.In particular,a strong optomechanical coupling increases the asymmetry of two windows,while a strong Coulomb coupling decreases the asymmetry.Moreover,the mechanical gain is further introduced.The results show that a singular point and a critical point appear in the transmission spectrum.An excellent optical amplification can be found at the singular point,and the corresponding transmission rate of the probe output field can reach the order of 10~4,and that the transmission rate after the rotation wave approximation can be as high as the order of 10~9.The transformation from the optical amplification to the optical absorption effect can be easily realized at the critical point.Finally,a significant fast-slow light effect appears near the singular point,and the group delay time reaches 10~5μs.Our work may open up a new way to realize the potential applications of counterrotating term in quantum precision measurement and quantum information processing.