arXiv:quant-ph/0505076 · Physical Review A
Bloch theory of entangled photon generation in nonlinear photonic crystals
William T. M. Irvine, M. J. A. de Dood, Dirk Bouwmeester
Abstract
We present a quantum-mechanical description of parametric down conversion and phase matching of Bloch waves in nonlinear photonic crystals. We discuss the theory in one-dimensional Bragg structures giving a recipe for calculating the down-converted emission strength and direction. We exemplify the discussion by making explicit analytical predictions for the emission amplitude and direction from a one-dimensional structure that consists of alternating layers of ${\mathrm{Al}}_{0.4}{\mathrm{Ga}}_{0.6}\mathrm{As}$ and air. We show that the emission is suitable for the extraction of polarization-entangled photons.