High Purcell factor generation of coherent on-chip single photons

Data from the manuscript "High Purcell factor generation of coherent on-chip single photons".<br>Abstract:<br>On-chip single-photon sources are key components for integrated photonic quantum technologies. Semiconductor quantum dots can exhibit near-ideal single-photon emission but this can be significantly degraded in on-chip geometries owing to nearby etched surfaces. A long-proposed solution to improve the indistinguishablility is by using the Purcell effect to reduce the radiative lifetime. However, until now only modest Purcell enhancements have been observed. Here we use pulsed resonant excitation to eliminate slow relaxation paths, revealing a highly Purcell-shortened radiative lifetime (22.7 ps) in a waveguide-coupled quantum dot–photonic crystal cavity system. This leads to near-lifetime-limited single-photon emission which retains high indistinguishablility (93.9%) on a timescale in which 20 photons may be emitted. Nearly background-free pulsed resonance fluorescence is achieved under π-pulse excitation, enabling demonstration of an on-chip, on-demand single-photon source with very high potential repetition rates.

来自手稿《高Purcell因子相干片上单光子产生》的数据。<br>摘要：<br>片上单光子源是集成光子量子技术的核心组件。半导体量子点可展现近乎理想的单光子发射，但在片上几何结构中，由于邻近的刻蚀表面，这种发射性能会显著退化。长期以来提出的提升不可区分性的解决方案是利用Purcell效应（Purcell effect）缩短辐射寿命（radiative lifetime）。然而，迄今为止仅观察到适度的Purcell增强。本文采用脉冲共振激发（pulsed resonant excitation）消除缓慢弛豫路径，揭示了波导耦合量子点-光子晶体腔系统（waveguide-coupled quantum dot–photonic crystal cavity system）中经Purcell效应大幅缩短的辐射寿命（22.7皮秒）。这导致近乎寿命受限的单光子发射，在可发射20个光子的时间尺度内仍保持高不可区分性（93.9%）。在π脉冲激发（π-pulse excitation）下实现了近乎无背景的脉冲共振荧光（resonance fluorescence），从而演示了具有极高潜在重复率的片上按需单光子源。