Semiconductor Cavity QED

腔量子电动力学（QED）是AMO物理学中最令人好奇和最基本的方面之一，它探索了耦合到谐振器电磁场的单个量子物体的量子动力学过程：珀塞尔效应，纠缠，量子/经典边界，量子信息科学和量子隐形传态。原子腔QED的最大实验瓶颈是原子的运动，最近才通过冷却和捕获减少，但没有停止。现在，半导体系统有机会比原子系统更好。腔QED光子晶体腔体积接近电介质的最小可能，品质因数非常高，量子点“原子”不移动。此外，该结构是完全集成的，即，它会保持在一起，所以可以反复使用。该项目的重点是这种新兴的能力，以调查固态纳米系统（腔/点），其中单个量子发挥决定性作用。这个小组是世界上第一个看到由于单个半导体量子点和光子晶体纳米腔之间的耦合而导致的真空拉比分裂的小组，正在探索两个研究领域。第一个目标领域是硅纳米梁腔和GaAs光子晶体纳米腔表面上的氧化钛原子层沉积的效果的调查。在沉积之前和之后，正在测量几个空腔的品质因数，以便收集关于其效果的统计数据。GaAs基腔的成功可能是减少耦合系统线宽的一种方法，现在主要由腔衰减率。另一个目标区域是观察到的银开口环谐振器阵列和非常靠近制造阵列的表面生长的量子阱之间的耦合的改变。在低温下，利用泵浦-探测光谱研究了量子阱和开口环谐振器之间的耦合对分离的依赖关系。这项研究是PI对加速半导体纳米结构辐射衰减的普遍兴趣的一部分，这是由珀塞尔在他的著名论文中最初提出的。 该项目为研究生提供从纳米技术到激光技术的最先进仪器方面的培训。

Cavity quantum electrodynamics (QED), one of the most curious and fundamental aspects of AMO physics, explores quantum dynamical processes for individual quantum objects coupled to the resonator's electromagnetic field: Purcell effect, entanglement, quantum/classical boundary, quantum information science, and quantum teleportation. The biggest experimental bottleneck for atomic cavity QED is the movement of the atom, only recently reduced, but not stopped, by cooling and trapping. Now a semiconductor system has a chance to be better than its atomic counterpart. The cavity QED photonic crystal cavity volume is near the minimum possible for a dielectric, the quality factor is very high, and the quantum dot "atom" does not move. Moreover the structure is totally integrated, i.e., it stays together, so it can be used over and over again. This project focuses on this emerging capability to investigate a solid-state nanosystem (cavity/dot) where individual quanta play decisive roles. This group, the first in the world to see vacuum Rabi splitting due to coupling between a single semiconductor quantum dot and a photonic crystal nanocavity, is exploring two research areas. The first target area is an investigation of the effect of atomic layer deposition of titanium oxide upon the surfaces of silicon nanobeam cavities and GaAs photonic crystal nanocavities. The quality factors of several cavities are being measured before and after the deposition in order to gather statistics on its effect. Success with GaAs-based cavities could be one way to reduce the coupled-system linewidths now dominated by cavity decay rates. The other target area is an alteration of the observed coupling between an array of silver split-ring resonators and a quantum well grown very close to the surface on which the array is fabricated. The dependence of the coupling upon separation between the quantum well and split-ring resonators will be studied at low temperature by pump-probe spectroscopy. This study is part of the PI's general interest in the acceleration of the radiative decay of semiconductor nanostructures by a nearby sub-wavelength metallic structure, as originally suggested by Purcell in his famous paper. This project provides training to graduate students on state-of-the-art instrumentation from nanotechnology to laser technology.