Cooperative decay rate and cooperative Lamb shift from a nanospherical configuration of two adjoining atomic species
Jamal T. Manassah
Accepted
The eigenmodes of a nanosphere configuration where the core is an ensemble of twolevel atoms with resonance frequency��C , and the shell is an ensemble of two-level atoms but with shifted resonant frequency ��B are obtained for different values of the ratio of the core radius to the shell outer radius as function of (��C ��� ��B ). I show that the eigenmodes belong to one of two branches. The dominant decay mode for superradiant emission may belong to either branch, depending on the system���s parameters. In instances of configurations where the CDR values for the two branches become equal, the cooperative exponential amplification (decay) is accompanied by temporal oscillations.