The Semi-classical Theoretical Study Of Optical Bistability In Three-level Atomic System

The Optical Bistability (OB) has always been an important research field of quantumoptics and nonlinear optics. Because of its potential application, for example, opticalbistable device may be widely used in high-speed optical communication, optical imageprocessing, optical storage, the optical limiter, and optical logic elements in the near future,a great number of people pay attention to the OB phenomenon which exhibit nonlinearcharacteristics. Especially since the Harris research team found EIT phenomenon whichsparked great interest in1991, the OB phenomenon of atomic system was studied morewidely in the semi-classical theory. In our thesis, within the semi-classical theory we haveintensive studies on the OB behavior of a three-level V-type atomic system inside aunidirectional ring cavity. In the thesis the specific work can be divided into three parts asfollows:(1) A brief introduction to the basic theory of OB, as well as the correlativeknowledge of optical bistable device;(2) Fairly detailed correlative basics of OB. Specifically including: description of thethree basic pictures for quantum system, the semi-classical theory of interaction betweenatoms and optical field, slowly varying envelope approximation;(3) We demonstrate the OB behavior of a three-level V-type atomic system inside aunidirectional ring cavity using a microwave field driving a hyperfine transition betweentwo upper excited states. We carry out the numerical calculations via nice Matlab codes,which show that the OB can be controlled by adjusting the intensity of the microwave andcoupling driving fields. Specifically, with the increase of the intensity of the coherentmicrowave driving field, the bistable threshold increases and the area of the hysteresiscycle becomes wider. By contrast, increasing the intensity of the coupling field leads to asignificant decreasing of the bistable threshold and the narrowing of the hysteresis loop.At the same time, the influences of the relative phase of three fields and the atomiccooperation parameter on the OB behavior are also discussed.