Quantum optics with deterministically positioned quantum emitters in a two-dimensional semiconductor

TYPESolid State Institute Seminar
Speaker:Professor Brian D. Gerardot
Affiliation:Inst.of Photonics and Quantum Sciences, SUPA, Heriot-Watt Univ.Edinburgh, UK,
Date:04.05.2017
Time:12:30 - 13:30
Location:Lidow 620
Remark:Host: Professor David Gershoni
Presentation:
Abstract:

The emergence of single quantum emitters in layered transition metal dichalcogenide semiconductors offers new opportunities to construct a scalable quantum architecture with a coherent light-matter interface. Here I will present results taking steps in this direction. First, using nanoscale strain engineering, we deterministically achieve a two-dimensional lattice of quantum emitters in an atomically thin semiconductor. We create point-like strain perturbations in mono-and bi- layer WSe2 which locally modify the band-gap, leading to efficient funnelling of excitons towards isolated strain-tuned quantum emitters. These emitters exhibit high-purity single photon emission that is stable and bright, yielding detected count rates up to 3 MHz. Next, we perform time-resolved photoluminescence, resonance fluorescence, and high-resolution photoluminescence excitation spectroscopy of these isolated, localized 2D excitons to characterize their dephasing mechanisms and unravel their origin. Finally, I will provide an outlook on investigations of the spin and valley coherence and prospects for integrated photonic chips incorporating quantum emitters in atomically-thin TMD semiconductors.