Physical Review Letters
Indistinguishable Tunable Single Photons Emitted by Spin-Flip Raman Transitions in InGaAs Quantum Dots
Yu He, Yu-Ming He, Y.-J. Wei, Xiao Qiang Jiang, M.-C. Chen, Fei-Lei Xiong, Y. Zhao, Christian Schneider, Martin Kamp, Sven Höfling, Chao‐Yang Lu, Jian-Wei Pan
Abstract
This Letter reports all-optically tunable and highly indistinguishable single Raman photons from a driven single quantum dot spin. The frequency, linewidth, and lifetime of the Raman photons are tunable by varying the driving field power and detuning. Under continuous-wave excitation, subnatural linewidth single photons from off-resonant Raman scattering show an indistinguishability of 0.98(3). Under π pulse excitation, spin- and time-tagged Raman fluorescence photons show an almost vanishing multiphoton emission probability of 0.01(2) and a two-photon quantum interference visibility of 0.95(3). Lastly, Hong-Ou-Mandel interference is demonstrated between two single photons emitted from remote, independent quantum dots with an unprecedented visibility of 0.87(4).