SHF: Small: Global Manipulation in Solid-State Quantum Information Processing - Protocols and Implementation

近年来，量子物理学被应用于研究计算复杂性问题，已成为计算机科学的一个新的前沿。根据量子力学定律运行的计算机硬件可以实现新的量子协议，并为某些计算困难的问题带来巨大的速度提升。 实现这种硬件的关键问题是实现对量子逻辑元件的高精度和快速控制，以便它们能够克服环境噪声的危险影响。 对于固态量子处理器，包括超导系统和半导体系统，这种控制通常是通过可调节的局部参数来实现的，其中需要仔细设计电路和与外部源的连接。 在这个项目中，量子全局模式将被利用来实现量子协议的有效实现。 这里，量子全局模是纳米级量子谐振器中的微波光子模，其具有毫米波长，可以同时与多个量子逻辑元件耦合，并且已经证明了微秒级量子相干时间。 同时，全局模也将被视为测量固态量子处理器中量子纠缠和量子相干效应的探针。 本课题将研究两个问题。首先，固态量子模拟器，可以模拟量子多体系统，涉及阵列的固态元件将被研究，其中的全局量子模式将作为一个控制器，以及在模拟器中的量子相变的检测器。 其次，一个通用的量子计算机的虚假的两个层次的超导系统的波动将被研究的全球模式可以提供个人控制，有效的耦合，和读出的波动状态。 硬件方面和软件方面都将进行研究。

Quantum physics has been applied to study problems in computing complexity in recent years, which has become a new frontier in computer science. Computer hardware that is operated according to the laws of quantum mechanics can realize novel quantum protocols and bring enormous speed-up for certain computationally hard problems. The key issue in implementing such hardware is in achieving highly accurate and fast control on the quantum logic elements so that they can beat the hazardous effects from the environmental noise. For solid-state quantum processors, including superconducting systems and semiconductor systems, such control is usually achieved via adjustable local parameters, where careful designing of the circuit and the connections to external sources are required. In this project, a quantum global mode will be exploited to achieve efficient implementation of the quantum protocols. Here, the quantum global mode is the microwave photon mode in a nanoscale quantum resonator that has millimeter wavelength, can couple with multiple quantum logic elements simultaneously, and has demonstrated microsecond quantum coherence times. Meanwhile, the global mode will also be considered as a probe to measure quantum entanglement and quantum coherence effects in the solid-state quantum processors. Two questions will be studied in this project. First, solid-state quantum simulators that can emulate quantum many-body systems involving arrays of solid-state elements will be studied, where the global quantum mode will act as a control as well as a detector of the quantum phase transitions in the simulators. Second, a universal quantum computer of spurious two-level fluctuators in the superconducting system will be studied where the global mode can provide individual control, effective coupling, and readout of the fluctuator states. Both the hardware aspect and the software aspect will be investigated.