Journal of Modern Optics
Theory of the Double-amplifier Interferometer
N. Hussain, R. Loudon
Abstract
We present an extension of Glauber's theory of the Mach-Zehnder interferometer with optical amplifiers placed in each of its internal paths. Conditions are derived for the achievement of maximum fringe visibility with amplifiers of general linear characteristics. The effects of the phase-conjugated and the phase-preserved components of the amplified light are elucidated for the contrasting cases of coherent and number-state inputs. Particular attention is paid to the minimization of amplifier noise in the limit of high gain.