We proposed a scheme for the generation of multi–atom W states with two-photon Jaynes-Cummings Model in ultrahigh-Q toroidal microcavities. We consider that the two modes, clockwise (CW) and counterclockwise (CCW) modes inside the microtoroidal resonator, can be produced by embedding Bragg grating in the microtoroidal.
We propose a scheme for the generation of three atom W states via the microtoroidal cavity-atom coupling system. This scheme can also be generalized to multi-atom W states. In this paper, three-atom resonant interact simultaneously with two counterpropagating cavity modes which can be produced by embedding Bragg grating in the microtoroidal. A single resonant interaction is required, thus this scheme is simple. Moreover, the required time to complete the whole process almost unchanges with increasing the number of atoms