Several emission features mark semiconductor quantum dots as promisingnon-classical light sources for prospective quantum implementations. Forlong-distance transmission and Si-based on-chip processing, the possibility tomatch the telecom C-band is decisive, while source brightness and highsingle-photon purity are key features in virtually any quantumimplementation. An InAs/InGaAs/GaAs quantum dot emitting in the telecomC-band coupled to a circular Bragg grating is presented here. This cavitystructure stands out due to its high broadband collection efficiency and highattainable Purcell factors. Here, simultaneously high brightness with afiber-coupled single-photon count rate of 13.9 MHz for an excitationrepetition rate of 228 MHz (first-lens single-photon collection efficiency≈17%for NA=0.6), while maintaining a low multi-photon contribution ofg(2)(0)=0.0052 is demonstrated. Moreover, the compatibility withtemperatures of up to 40 K attainable with compact cryo coolers, furtherunderlines the suitability for out-of-the-lab implementations.
Publication: Bright Source of Purcell-Enhanced, Triggered, Single Photons in the Telecom C-Band
Nawrath, C., Joos, R., Kolatschek, S., Bauer, S., Pruy, P., Hornung, F., Fischer, J., Huang, J., Vijayan, P., Sittig, R., Jetter, M., Portalupi, S. L., Michler, P.
Advanced Quantum Technologies (2023)
Contact person: R.Joss