Research On Photon Blockade Of Different Effective Energy State Systems Affected By Environment

In recent years,photon blocking has become one of the attracting issues in quantum optics.When a single two-level atom interacting with a single-mode cavity is affected by a classical field interacts,the resonance absorption of the subsequent photons will be hindered due to the nonlinear characteristics of a single photon where the system is in the resonance of dressed states.Thus that will lead to photon blockade.Photon blockade is widely used,including single photon converter,optical communication,optical quantum computer,photon routing,and other emerging technologies.Photon blockade is directly related to anti-bunching effect of photons.In the resonant transition of two photons,the bunching effect and the anti-bunching effect sometimes alternate,which is closely related to the coupling coefficient ~g and the classical driving strengthε.Firstly,the effective dynamics of the JC model is analyzed.The state space is truncated effectively for the atom-cavity interacting system influence by the environment.The transitions brought about by the classical driving are discussed.For the interception of 8 states,the effective Hamiltonian is given by using the Fr?hlich transformation,as well as the level shifts of the dressed level and all effective strength.The transition between|ψ_+(1)〉and|ψ_-(3)〉is analyzed by solving the master equation.The one-order and second-order coherent functions of double photon processing are obtained.The photon blockade is analyzed by modulating the coupling parameters.According to a given driving strengthεof the classical field,the second-order coherent function demonstrates antibunching by adjusting the dipole coupling.That means the photon blockade occurring.The results show that the dipole coupling for the 6 states truncation has to be considerably larger than the case of 8 states truncation.For a given classical driving,the second-order coherent function of the 8 states truncation is more sensitive to the dipole coupling than that of the 6 states.That is the photon blockade can be observed more easily.