Noiseless amplification in cavity-based optical systems with an internal two-photon process. I. General approach

We study the features of noiseless amplification in a general class of optical systems, characterized by an intracavity nonlinearity which induces a two-photon process, in the limit where the damping constant of the mode which undergoes the two-photon process greatly exceeds all other relaxation rates of the system. By applying a previously formulated analytical approach, we write the universal-form expressions for the linear amplification factor and the noise figure. Noiseless amplification is attainable under resonance conditions.