Entangled Photon Pair Emission and Interference from Single Quantum Dots

We review in this chapter our recent realization and development of en- tangled light emission from individual InAs quantum dots. We describe how energetic which-path information is circumvented by attention to the confinement energy of the dot, resulting in generation of entangled photon pairs with up to 76% fidelity. Improvements in device design are detailed that reveal the importance of controlling the charge of the dot in order to maximize both emission intensity and fidelity. Finally we present interferometric measurements of the entangled biphoton state that shows a two-fold enhancement of the de Broglie wavelength com- pared to single photons