Overcoming the Rate-Directionality Trade-off: A Room-Temperature Ultrabright Quantum Light Source

Abstract

Deterministic GHz-rate single photon sources at room-temperature would be essential components for various quantum applications. However, both the slow intrinsic decay rate and the omnidirectional emission of typical quantum emitters are two obstacles towards achieving such a goal which are hard to overcome simultaneously. Here we solve this challenge by a hybrid approach, using a complex monolithic photonic resonator constructed of a gold nanocone responsible for the rate enhancement, and a circular Bragg antenna for emis-1 arXiv:2010.15016v2 [quant-ph] 3 Nov 2020 sion directionality. A repeatable process accurately binds quantum dots to the tip of the antenna-embedded nanocone. As a result we achieve simultaneous 20-fold emission rate enhancement and record-high directionality leading to an increase in the observed brightness by a factor as large as 580 (120) into an NA = 0.22 (0.5). We project that such miniaturised on-chip devices can reach photon rates approaching 2.3 × 10 8 single photons/second thus enabling ultrafast light-matter interfaces for quantum technologies at ambient conditions.

Bright semiconductor single-photon sources pumped by heterogeneously integrated micropillar lasers with electrical injections

“…Photons emitted from the QD in the center of CBG are mostly confined in the suspended membrane. Due to the presence of second-order Bragg gratings, parts of the emitted photons from the QD are scattered upwards for efficient collections and the others are reflected back to form a cavity for enhancing the strength of light-matter interactions [33][34][35][36][37][38] . To optically pump the QD-CBG SPS, we explore electrically-injected micropillar lasers 39 With the above device design, we further explore the optical performance of a single-QD in the hybrid cavities by modeling the extraction efficiency and the Purcell factor, as shown in Fig.…”

Bullseye dielectric cavities for photon collection from a surface-mounted quantum-light-emitter

“…To quantify the effect of increased cavity periods, the effective enhancement factor (EF) 31 (or the brightness enhancement 21 ) is investigated. It includes not only the enhancement of the emission, but also the excitation.…”

“…Recently, a hybrid structure based on a bullseye has been reported in which a high Purcell factor over a broad range of wavelengths with high collection efficiency is achieved 21 . Inspired by the bullseye pattern, defects in photonic crystals were recently proposed as a new platform for extremely high Purcell factor with high collection efficiency 22 .…”

Bright Semiconductor Single-Photon Sources Pumped by Heterogeneously Integrated Micropillar lasers with Electrical Injections

“…Photons emitted from the QD in the center of CBG are mostly confined in the suspended membrane. Due to the presence of second-order Bragg gratings, parts of the emitted photons from the QD are scattered upwards for efficient collections and the others are reflected back to form a cavity for enhancing the strength of lightmatter interactions 1,2,[34][35][36][37] . To optically pump the QD-CBG SPS, we explore electrically-injected micropillar lasers 38 consisting of quantum wells sandwiched between two distributed Bragg Reflectors (DBRs) [Fig.…”