Microfiber-microcavity system for efficient single photon collection.

Chang-Min Lee,Martin Kamp,Yong-Hee Lee,Mireu Lee,Hee-Jin Lim,Sebastian Maier,Christian Schneider,Sven Höfling

doi:10.1364/oe.24.023471

Abstract

Single photon sources are key components for various quantum information processing. For practical quantum applications, bright single photon sources with efficient fiber-optical interfaces are highly required. Here, bright fiber-coupled single photon sources based on InAs quantum dots are demonstrated through the k-vector matching between a microfiber mode and a normal mode of the linear photonic crystal cavity. One of the modes of the linear photonic crystal cavity whose k-vector is similar to that of the microfiber mode is employed. From independent transmission measurement, the coupling efficiency directly into the fiber of 58% is obtained. When the quantum dot and cavity system is non-resonantly pumped with 80 MHz pulse train, a raw count rate of 1.81 MHz is obtained with g(2)(0) = 0.46. Resonant pump is expected to improve the rather high g(2)(0) value. Time-resolved photoluminescence is also measured to confirm the three-fold Purcell enhancement. This system provides a promising route for efficient direct fiber collections of single photons for quantum information processing.

Highlights

Triggered single photon sources (SPSs) have been actively pursued over the past two decades, motivated by quantum information processing such as quantum key distribution [1] and quantum computing [2]
There was some discrepancy between the highest η of the fabricated cavities and the η of the bright SPS due to the fluctuation of the η and the randomness of the quantum dots (QDs)-cavity coupling
If we introduce strain tuning of the QD [40,41,42] for better spectral matching or site-controlled QDs [43] for deterministic spatial matching, the efficiency of QD-cavity coupling can be made higher and a QD can be coupled to a cavity with higher η

Summary

Introduction

Triggered single photon sources (SPSs) have been actively pursued over the past two decades, motivated by quantum information processing such as quantum key distribution [1] and quantum computing [2]. "Efficient Single-Photon Sources Based on Low-Density Quantum Dots in Photonic-Crystal Nanocavities," Phys. "Efficient outcoupling of high-purity single photons from a coherent quantum dot in a photonic-crystal cavity," Phys. "Deterministic generation of bright single resonance fluorescence photons from a Purcellenhanced quantum dot-micropillar system," Optics Express 23, 32977 (2015).

Results

Conclusion