Purcell‐Enhanced Single‐Photon Emission in the Telecom C‐Band

Abstract

Purcell‐enhanced quantum dot single‐photon emission in the telecom C‐band from InAs quantum dots inside circular Bragg grating cavities is shown. The InAs quantum dots are grown by means of molecular beam epitaxy on an InP substrate and are embedded into a quaternary In0.53Al0.23Ga0.24As membrane structure. In a post‐growth flip‐chip process with subsequent substrate removal and electron beam‐lithography, circular Bragg grating (“bullseye”) resonators are defined. Micro‐photoluminescence studies of the devices at cryogenic temperatures of K reveal individual quantum dot emission lines into a pronounced cavity mode. Time‐correlated single‐photon counting measurements under above‐band gap excitation yield Purcell‐enhanced excitonic decay times of ps corresponding to a Purcell factor of . Pronounced photon antibunching with a background limited is observed, which demonstrates that the light originated mostly from one single quantum dot.

Purcell-enhanced single photons at telecom wavelengths from a quantum dot in a photonic crystal cavity

“…1 implying a spatial overlap between emitter and cavity of only 30% . This value is comparable to the Purcell factors measured in bullseye resonator cavity structures where a F P of 3.0 ± 0.7 has been measured for a QD in an InAs/InGaAs/GaAs system 45 and a F P of 6.7 ± 0.6 has been measured for InAs QDs embedded in an InAlGaAs membrane 46 . An F P of 5 has been observed for a InAs QDs in an InP membrane in a line-defect PhCC.…”

Strain‐Free GaSb Quantum Dots as Single‐Photon Sources in the Telecom S‐Band

“…[20] Over the last few years, several QD material platforms like indium (gallium) arsenide (In(Ga)As)/ GaAs and indium arsenide (InAs)/indium phosphide (InP) [21] have emerged as resources for non-classical light in the wavelength range ≈1550 nm. [22] In particular, the use of a metamorphic buffer (MMB) layer was utilized to shift the emission of InAs QDs into the telecom range [23] creating single photons [24,25] and polarization-entanglement. [26] First attempts to increase collection efficiency in free space [27,28] as well as fiber-coupled by integrating telecom InAs QDs into photonic structures [29] have been demonstrated, and first steps into plug and play devices for quantum key distribution (QKD) in the telecom O-band have been realized.…”