C.L.A. Hooijer

Mode density inside an omnidirectional mirror is heavily directional but not small

We show that ominidirectional reflection is not a sufficient signature of a photonic bandgap. Although dramatic angular redistribution takes place, the mode density of the electromagnetic field is hardly altered within the ominidirectional reflection range but rather has characteristics typical of a waveguide. The strikingly large polarization anisotropy is due to the huge dielectric contrast but not to a photonic bandgap.

Spontaneous emission in a V-type three-level atom driven by a classical field

Abstract We have studied the spectrum of spontaneous emission of a V-configuration three-level atom, whose two upper levels are linked by a classical driving field and their energy spacing is much larger than the spontaneous emission widths. It is shown that the spectrum can be controlled by the driving field and peaks with subnatural linewidth can be produced.

Spontaneous emission in multilayer semiconductor structures

A theoretical analysis of spontaneous emission from a quantum well in dielectric multilayer structures, especially the influence of dielectric geometry on the relative intensities of guided and radiation modes and on polarization, is presented. We first discuss a relatively simple three-layer case, and subsequently a technologically more interesting five-layer structure that has been proposed for a high-power laser. The expression for the partial as well as total, emission rates is derived within a broader framework of coupled Heisenberg equations of motion for charge carriers and the quantized electromagnetic field. Thereby, the explicit mode decomposition of the Green tensor is avoided. Still, the beta factor for individual guided modes, which is a relevant quantity for the lasing threshold of a device, can be identified and a competition between modes is shown to exist in specific cases.

Properties of spontaneous emission in semiconductor structures

A quantum mechanical description is presented of the electromagnetic field produced by a semiconductor quantum well within a passive dielectric multilayer structure. The method is suitable to deal with relatively complicated structures as it avoids an explicit mode decomposition of the electromagnetic field. Instead, only the classical Greens tensor, which is characteristic of a certain passive structure, is required. Our central result is a general expression for the spontaneous emission rate, that we apply to a quantum well embedded in a three-layer (waveguide) structure. The dependence of the spontaneous emission rate on the thickness of the middle layer, or on the position of the quantum well in it, is shown to be smooth. But the separate continuous (radiation modes) and discrete (guided modes) contributions to this rate show peculiar cusps as a function of this thickness, and these discontinuities are analyzed.