Quantum and classical amplifier theory

An abstract theory of quantum linear amplifiers in which ''in'' and ''out'' Bose operators are related by a linear transformation with added quantum noise has been presented by a previous author. This theory has a purely formal basis, and is not related to any physically constructed amplifier model. In this paper, a Hamiltonian formulation of dissipative amplifiers, which can be formulated classically and quantum mechanically, is used to investigate via master equation methods, the ways in which this author's results are implemented in quantum amplifiers and to include the effects of thermal noise as well