Semiconductor Cavity QED

半导体腔QED

• 批准号: 1205301
• 负责人: Galina Khitrova
• 金额: $ 45万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1205301&HistoricalAwards=false
• 关键词: Semiconductor; Cavity; QED

This project builds on the breakthrough observation of accelerated decay (Purcell) of the resonant near-field coupling between two "oscillators" -- one the typical gain of a single semiconductor quantum well (InGaAs) and the other the very strong absorption of an array of metallic (silver) split ring resonators with very large dipole moments. The observation of this coupling is possible because of the giant vacuum field produced by the split ring resonator having a mode volume, V, a thousand times smaller than the minimum V for a photonic crystal slab cavity fabricated in a dielectric (silicon or GaAs). One can predict from the quantum well results that one should even be able to see coupling between such a resonator and a single stationary quantum dot -- the principal goal of this project -- thus opening a new regime for light-matter (resonator-emitter) interaction. Usually, Purcell enhancement (proportional to Q/V) is achieved in a dielectric cavity of very high quality factor, Q. Thus, enhancement occurs only for an emitter lying within the very narrow range of frequencies of the cavity peak. In contrast here, the Q of the split ring resonator is only of order 10; nonetheless, the Purcell enhancement is still large because of the metallic resonator's very tiny mode volume. Consequently, emitters with transitions lying anywhere within the very broad resonance are subjected to a very large vacuum field and have their spontaneous emission accelerated, resulting in overlap of their radiatively broadened spectra.The results of fundamental atomic and semiconductor cavity QED research have had lasting impact on semiconductor laser technology. A specific ongoing example is the development of the vertical-cavity surface-emitting laser (VCSEL) pioneered by a graduate from this group. Single quantum dot cavity QED enables nanoscience to go beyond traditional nonlinear optics and laser physics into a new regime with dynamical processes and active devices now involving quantum dots and photons taken one by one. This research on quantum optics in monolithic solid-state cavities would continue to forge new links between the AMO and nanophotonics communities begun by the observation of strong coupling reported in a highly-cited Nature article.

该项目建立在对两个“振荡器”之间谐振近场耦合的加速衰变（Purcell）的突破性观察之上——一个是单个半导体量子阱（InGaAs）的典型增益，另一个是具有非常大偶极矩的金属（银）裂环谐振器阵列的非常强的吸收。这种耦合的观察是可能的，因为开口环谐振器产生的巨大真空场的模体积 V 比在电介质（硅或砷化镓）中制造的光子晶体板腔的最小 V 小一千倍。人们可以从量子阱结果中预测，人们甚至应该能够看到这种谐振器和单个固定量子点之间的耦合——这是该项目的主要目标——从而为光与物质（谐振器-发射器）相互作用开辟了一种新的机制。通常，Purcell 增强（与 Q/V 成比例）是在品质因数 Q 非常高的介电腔中实现的。因此，增强仅发生在位于腔峰值频率非常窄的范围内的发射极上。相比之下，开口环谐振器的 Q 值仅为 10 阶；尽管如此，由于金属谐振器的模式体积非常小，珀塞尔增强仍然很大。因此，跃迁位于非常宽的谐振范围内任何位置的发射器都会受到非常大的真空场的影响，并加速其自发发射，从而导致其辐射展宽的光谱重叠。基础原子和半导体腔 QED 研究的结果对半导体激光技术产生了持久的影响。一个正在进行的具体例子是由该小组的一名毕业生率先开发的垂直腔表面发射激光器（VCSEL）。单量子点腔 QED 使纳米科学能够超越传统的非线性光学和激光物理学，进入一个新的领域，其动态过程和有源器件现在涉及量子点和光子的逐一拍摄。这项关于单片固态腔中量子光学的研究将继续在 AMO 和纳米光子学界之间建立新的联系，该研究始于一篇被高度引用的《自然》文章中报道的强耦合观察。