The entanglement of two dipole-dipole coupled atoms induced by nondegenerate two-mode thermal noise

We investigate the entanglement properties of a system of two dipole-dipole coupled two-level atoms resonantly interacting with a two-mode thermal field in a high-Q cavity. We obtain the evolution operator for this system in an analytical form, and use it to evaluate the atom-atom entanglement through the calculation of the negativity. The results show that the atom-atom entanglement is dependent on cavity field intensity and dipole interaction strength. We find that the dipole interaction can produce a considerable amount of entanglement between the two atoms.