Phonon limit to simultaneous near-unity efficiency and indistinguishability in semiconductor single photon sources

Summary form only given. Semiconductor quantum dots have recently emerged as a leading platform to efficiently generate highly indistinguishable photons [1-3], and this work addresses the timely question of how good these solid-state sources can ultimately be. Based on a microscopic theory, we establish the crucial impact that lattice relaxation has in these systems, which gives rise to a broad phonon sideband in bulk quantum dot emission spectra, as seen in Fig. (1) a. We show how both the indistinguishability and efficiency of a single photon source based on such a quantum dot in a modified photonic environment depends on the way in which this incoherent sideband is removed from the spectra [4].