Characterization Method for Excitation Efficiency of Semiconductor Quantum Dots

Quantum dots are promising semiconductor sources of nonclassical light. Quantum dots can be used to, on-demand, generate single photons [1] and photon pairs [2]. They can generate pairs of photons entangled in polarization [3] and time bin [4]. Furthermore, the photons emitted by a quantum dot can be employed in a broad range of applications including optical quantum computation, long-distance quantum communication, and protocols like quantum state teleportation. In particular, the possibility to excite the quantum dots resonantly is one of the most important assets of this system. The resonant excitation is the process responsible for the high photon generation efficiency. In combination with photonic structures that enables high photon extraction efficiency, quantum dots can lay the basis for accomplishing very high efficiency sources of quantum light [5].