在应用物理量子点单光子源

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单个量子点定位在一个光学共振器来创建一个量子点单光子源。这是一个单光子源上可用的需求。量子点,运营商可以兴奋的作用对激光脉冲。一个光子是一个激发衰变时释放自发发射的结果。因为之间的交互作用,量子点的发射与单个激发能量从一个与许多不同励磁。结果,一束激光脉冲可以确定性产生一个单一的激励,以及量子点转换成非经典的光源,发出光子光子anti-bunching一次和展品。通过测量强度二阶相关函数,它可以证明单个光子的发射。集成光学腔可以提高量子点的自发发射的光子的速度释放。腔也导致一个明确定义的光学发射模式,提高光子源的效率。自从21世纪,量子信息科学的兴趣的增加,导致研究各种单光子源的增加。 Early single-photon sources, including the 1985-first-reported heralded photon sources, are based on non-deterministic processes.

2000年,一个量子点在micro-disk结构被用来创建一个单光子源。之后,源合并到其他架构如micro-pillars或光子晶体。DBRs分布式布拉格反射镜()被用来提高发射效率和使发射一个明确的方向。这仍然是一个技术问题对于大多数量子点单光子设备在低温下操作。实现卓越的电信波长量子点单光子源光纤通信的应用程序是另一个艰巨的任务。根据第一项研究Purcell-enhanced telecom-wavelength量子点单光子发射的二维光子晶体谐振腔品质因数2000,发射率和强度增加了五、六倍,分别。激发态或所谓的激发,产生一个电子在半导体从价带兴奋传导带。一个光子是这个兴奋经历自然放射性衰变时释放。可以确保没有超过一个励磁发生在一个量子点量子点以来离散能级。量子点是一个单光子发射体结果; making an effective single-photon source requires a number of technical challenges, including ensuring that the emission from the quantum dot is gathered effectively. The quantum dot is positioned in an optical cavity to do that. Two DBRs in a micro-pillar, for instance, may make up the cavity. The Jayne’s Cummings model can then be used to approximate the system. Only one mode of the optical cavity interacts with the quantum dot in this paradigm. The optical mode's frequency is clearly identified. If a polarizer aligns the photons' polarization, it blurs their differences. A vacuum Rabi oscillation is the Jayne’s Cummings Hamiltonian's solution. An excitation-polariton is a vacuum Rabi oscillation of a photon that has interacted with an excitation. Making sure that there can only be one excitation occurring in the cavity at once will avoid the possibility of two photons emitting simultaneously. A quantum dot can only undergo one excitation due to its discrete energy states.