Cavity Polarization Tuning for Enhanced Quantum Dot Interactions
Cavity enhanced interactions of light and matter have promising applications in quantum information technology. In particular, semiconductor quantum dots are extremely good candidates for single photon sources. Quantum dots have strong optical properties and can be directly embedded into photonic devices. Micropillar cavities with embedded quantum dots can be grown and fabricated, all with the use of mature semiconductor technology. Typically, microcavities are fabricated with a finite polarization mode splitting. Such splitting is detrimental in most applications, including the generation of single photons. The mechanisms that produce birefringence in semiconductor micropillar cavities are discussed in detail, and methods to eliminate such effects are discussed. A fine tuning method is presented, which is used to independently tune the cavity polarization splitting and quantum dot resonance. The fine tuning method makes use of the linear electro-optic effect to alter the birefringence of a single mirror. With high resolution reflection spectroscopy, the dynamics of a quantum dot in a polarization degenerate cavity are studied. Interactions are discussed, both in the context of classical, and quantum mechanical interactions.