Ota Yasutomo, Ohta Ryuichi, Kumagai Naoto, Iwamoto Satoshi, Arakawa Yasuhiko
Institute for Nano Quantum Information Electronics, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
Phys Rev Lett. 2015 Apr 10;114(14):143603. doi: 10.1103/PhysRevLett.114.143603. Epub 2015 Apr 8.
We report the observation of the vacuum Rabi splitting of a single quantum emitter by measuring its direct spontaneous emission into free space. We use a semiconductor quantum dot inside a photonic crystal nanocavity, in conjunction with an appropriate cavity design and filtering with a polarizer and an aperture, enabling the extraction of the inherently weak emitter's signal. The emitter's vacuum Rabi spectra exhibit clear differences from those measured by detecting the cavity photon leakage. Moreover, we observe an asymmetric vacuum Rabi spectrum induced by interference between the emitter and cavity detection channels. Our observations lay the groundwork for accessing various cavity quantum electrodynamics phenomena that manifest themselves only in the emitter's direct spontaneous emission.
我们通过测量单个量子发射器向自由空间的直接自发辐射，报告了对其真空拉比分裂的观测结果。我们使用光子晶体纳米腔中的半导体量子点，结合适当的腔设计，并通过偏振器和孔径进行滤波，从而能够提取本质上微弱的发射器信号。发射器的真空拉比光谱与通过检测腔光子泄漏所测得的光谱表现出明显差异。此外，我们观察到由发射器和腔检测通道之间的干涉引起的不对称真空拉比光谱。我们的观测结果为研究各种仅在发射器直接自发辐射中表现出来的腔量子电动力学现象奠定了基础。
