The Degenerate Parametric OscillatorI: Squeezed States

Abstract

Volume 1 of this book introduced the formalism of open systems in quantum optics as it existed in the early 1980s, two decades after the invention of the laser. In it we met the operator master equation, the quantum regression formula, and the phase-space methods, based on the P, Q, and Wigner representations, that provide “classical” visualizations of the fluctuations of the radiation field—the so-called quantum–classical correspondence. We also met Fokker–Planck equations and stochastic differential equations, and the various methods of classical statistical physics that help with the analysis within the phase-space representations. The application of all these things was illustrated by two classic examples: resonance fluorescence and the single-mode laser.