Implementing a Quantim CNOT Gate Using Solid State Cavity QED

将单光子技术与半导体电光器件相结合，研究了一种量子CNOT门的设计方案。这种门是量子计算机和量子通信系统的基本组成部分。纳米制造和材料生长概念将被应用于制造光学微腔结构，其中嵌入了纳米级半导体结构形式的人造原子，称为量子点。一个量子点，如果位于腔的中心并且处于腔谐振频率，将以这样一种方式与入射光子相互作用，光子偏振将与量子点的电子状态纠缠在一起。这种相互作用建立了量子CNOT门；光子的量子态随电子的量子态而改变。研究课题直接关系到微光电子工业以及半导体中受限电子性质的基础研究。在经典和量子信息存储和处理方面的潜在应用有望从这个项目开始。由于这些相互作用是在单光子水平上进行的，因此这些装置原则上是非常节能的。然而，应该提到的是，本研究确实需要低温操作条件。还将考虑基于不同腔体设计和在室温下保持活动的不同光发射器的替代实现。

By combining single-photon technology with semiconductor electro-optical devices we investigate a scheme for a quantum CNOT gate. Such a gate is a fundamental building block of quantum computers and quantum communication systems. Nanofabrication and material-growth concepts will be implemented to create optical micro cavity structures with embedded artificial atoms in the form of a nanoscale semiconductor structure, called a quantum dots. A quantum dot, if positioned at the center of the cavity and at the cavity resonant frequency, will interact with an incoming photon in such a way that the photon polarization will become entangled with the electronic state of the quantum dot. This interaction establishes the quantum CNOT gate; the quantum state of the photon is changed depending on the quantum state of the electron.The research topic directly relates to the micro optoelectronics industry as well as to fundamental studies of confined electron properties in semiconductors. Potential applications in classical and quantum information storage and processing are expected to follow from this project. Since the interactions are at the single photon level, the devices will in principle be very energy efficient. It should however be mentioned that this study does require low-temperature operation conditions. Alternative implementations based on different cavity designs and different optical emitters that remain active a room temperature will also be considered.