Physical Review A
Suppression of two-photon absorption by quantum interference
Min Yan, Edward G. Rickey, Yifu Zhu
Abstract
Electromagnetically induced transparency may lead to suppression of two-photon absorption in a four-level atomic system. This phenomenon is manifested by destructive quantum interference among multiple excitation paths created by a coherent coupling field. We report an experimental observation of such suppression of two-photon absorption in cold ${}^{87}\mathrm{Rb}$ atoms.