Kreinberg Sören, Grbešić Tomislav, Strauß Max, Carmele Alexander, Emmerling Monika, Schneider Christian, Höfling Sven, Porte Xavier, Reitzenstein Stephan
1Institut für Festkörperphysik, Technische Universität Berlin, 10623 Berlin, Germany.
2Institut für Theoretische Physik, Technische Universität Berlin, 10623 Berlin, Germany.
Light Sci Appl. 2018 Jul 25;7:41. doi: 10.1038/s41377-018-0045-6. eCollection 2018.
Two-level emitters are the main building blocks of photonic quantum technologies and are model systems for the exploration of quantum optics in the solid state. Most interesting is the strict resonant excitation of such emitters to control their occupation coherently and to generate close to ideal quantum light, which is of utmost importance for applications in photonic quantum technology. To date, the approaches and experiments in this field have been performed exclusively using bulky lasers, which hinders the application of resonantly driven two-level emitters in compact photonic quantum systems. Here we address this issue and present a concept for a compact resonantly driven single-photon source by performing quantum-optical spectroscopy of a two-level system using a compact high- microlaser as the excitation source. The two-level system is based on a semiconductor quantum dot (QD), which is excited resonantly by a fiber-coupled electrically driven micropillar laser. We dress the excitonic state of the QD under continuous wave excitation, and trigger the emission of single photons with strong multi-photon suppression ( ) and high photon indistinguishability ( = 57±9%) via pulsed resonant excitation at 156 MHz. These results clearly demonstrate the high potential of our resonant excitation scheme, which can pave the way for compact electrically driven quantum light sources with excellent quantum properties to enable the implementation of advanced quantum communication protocols.
双能级发射体是光子量子技术的主要组成部分，也是探索固态量子光学的模型系统。最有趣的是对这类发射体进行严格的共振激发，以便相干地控制它们的占据情况并产生接近理想的量子光，这对于光子量子技术的应用至关重要。迄今为止，该领域的方法和实验完全是使用笨重的激光器进行的，这阻碍了共振驱动的双能级发射体在紧凑型光子量子系统中的应用。在此，我们解决这一问题，并通过使用紧凑型高 微激光器作为激发源对双能级系统进行量子光学光谱研究，提出了一种紧凑型共振驱动单光子源的概念。该双能级系统基于一个半导体量子点（QD），它由光纤耦合的电驱动微柱激光器进行共振激发。我们在连续波激发下修饰量子点的激子态，并通过在156兆赫兹的脉冲共振激发触发具有强多光子抑制（ ）和高光子不可区分性（ = 57±9%）的单光子发射。这些结果清楚地证明了我们的共振激发方案的巨大潜力，它可为具有优异量子特性的紧凑型电驱动量子光源铺平道路，以实现先进的量子通信协议。
