Physical Review A
Quantization of evanescent electromagnetic waves based on detector modes
Tetsuya Inoue, Hirokazu Hori
Abstract
The problem of field quantization in a half space is discussed based on the detector modes, which provide a useful basis for the study of atomic or molecular interaction with radiation modes involving evanescent electromagnetic waves. The detector modes, each of which involves a single outgoing wave, are introduced in terms of the time-reversal and spatial-rotation transforms of the widely used triplet modes given by Carniglia and Mandel. The derivation of the orthogonal relation for the detector modes is therefore straightforward. We represent the creation and annihilation operators for the detector modes in terms of those for the triplet modes, and obtain the field operator, Hamiltonian, number operator, and pseudomomentum operator. Based on this formalism, we evaluate the differential radiation probability for atomic dipole radiation near a dielectric surface. The evaluation of the final-state mode density is straightforward for the detector modes involving single outgoing waves. With respect to the image dipole picture, the quantum-to-classical correspondence is clear in the detector-mode formalism.