Detecting a single atom in a cavity using the ${\chi }^{(2)}$ nonlinear medium

Dong-Liang Chen, Ye-Hong Chen, Yang Liu +3

We propose a protocol for detecting a single atom in a cavity with the help of the ${\chi }^{(2)}$ nonlinear medium. When the ${\chi }^{(2)}$ nonlinear medium is driven by an external laser fi…