The Second-Order Correlation Function for Two-Level Systems

Jaewan Kim, Heung‐Ryoul Noh

We present analytical solutions for the second-order correlation function [ g (2 )( τ )] for light scattered from a two-level atom driven by laser light with arbitrary detuning and the Rabi frequency. By solving the optical Bloch equations for a two-level atom, we obtain analytical solutions for the populations that are subsequently used for calculating g (2 )( τ ). We also obtain g (2)( τ ) for special cases, such as zero detuning or weak laser intensity, directly from the general analytical solutions for g (2 )( τ ).

Alexander A. Ovchinnikov, V. Ya. Krivnov

WU Dao-yong

We study the two-excitation system comprising two two-level atoms resonantly interacting with two coupled cavities.The evolution of the state vector of the system is given.By means of the numerical calculations,we investigate the evolution of the second-order correlation function of the field and that of Mandel Q function.The influences of coupling constant between cavities and state-selective measurement of the atom on the second-order correlation function and Mandel Q function are discussed.The results obtained show that the second-order correlation function or Mandel Q function has a nonlinear relation with increasing of the cavity-cavity coupling coefficient.On the other hand,the sub-Poissonian distribution of the field can be strengthened through the state-selective measurement on the atom.

S. Rebić, A. S. Parkins, S. M. Tan

We analyze the properties of the second-order correlation functions of the electromagnetic field in atom-cavity systems that approximate two-level systems. It is shown that a recently developed polariton formalism can be used to account for all the properties of the correlations, if the analysis is extended to include two manifolds---corresponding to the ground state and the states excited by a single photon---rather than just two levels.

Akihiko Matsuyama