Signal Analysis Based On Optomechanical Systm

Quantum information has become an important new direction of information science research in the 21 st century with its physical absolute confidentiality and parallelism.Quantum optics,which studies the photon bits of flying and interact with other substances,has become an important part of the study of quantum information.The study of quantum optics involves a wide range of interactions between light and atomic molecules,crystal structures,and mechanical modes.In recent years,the experimental realization of optical interaction and optomechanical structure in microcavities has provided important support for the practical application of optomechanics in quantum information.The optomechanics in microcavity has great potential for high-precision manipulation of photons with its printable and high-quality characteristics.Also,it is an important structure for the fabrication of quantum information processing devices.Nowadays,the application of optomechanical systems in quantum information science has increasingly become an important topic in quantum science research.The interaction between the high-frequency electromagnetic field and the low-frequency mechanical mode in the optomechanical system is nonlinear,which determines that the motion of the system is non-resonant,and the system must have high-order sidebands.In order to understand the frequency characteristics of the optomechanical system,the Fourier analysis method is usually used to study the frequency characteristics of the system.Through Fourier analysis,one can clearly see the frequency behavior of the optomechanical system.However,as a parameter of the optomechanical system,the frequency of the system can also be changed with time.Obviously,it is difficult to observe the behavior of the optomechanical system frequency conversion directly through the Fourier transform.In fact,we have no way in the optomechanical system to directly determine that the spectrum of the system is stable.Therefore,to carefully study the spectral characteristics of the optomechanical system,we should choose the method of time-frequency analysis.Therefore,in the research of this thesis,the output signal of the optomechanical system is processed by time-frequency analysis by continuous wavelet transform,and the oscillation phenomenon of high-order sidebands is observed.In this paper,we first introduce the theoretical basis and experimental implementation of the optomechanical system.Then,we introduce and contrast two basic methods of signal analysis,namely Fourier transform analysis and wavelet transform analysis.Then,we used the above two methods to conduct the following research based on the optomechanical model introduced above:Firstly,we obtain the time evolution characteristics of the optomechanical system in each degree of freedom by numerically solving the dynamic equations of the system.Secondly,we obtain the frequency characteristics of the optomechanical system by performing Fourier transform and wavelet transform on the output signals respectively.By comparing the spectrum with the Fourier transform,we find that the system will produce new characteristics of oscillation in the frequency domain.We have analyzed the generation of this oscillation,which is believed to be caused by the instability of the coupling of the optomechanical system.In short,our research has brought a new understanding of the system,and more new phenomena can be observed through time-frequency analysis.This is a further study of quantum communication based on optomechanical system and optical frequency comb.