The,project supported by the China Postdoctoral Science Foundation under Grant No. 2004036309, National Natural Science Foundation of China under Grant Nos. 10447133 and 10574133, and HongKong K.C. Wong Education Foundation
We study the propagation of a quantum probe light in an ensemble of tripod level atoms when the atoms are coupled to two other classical control fields. First we calculate the dispersion properties, such as susceptibi...