Coherent Control of Spin Qubits in High Density Quantum Dot Arrays in Silicon

在过去的60年里，计算能力呈指数级增长，这一切都归功于晶体管的不断改进，晶体管是计算机的组成部分。然而，我们现在开始看到晶体管技术进步带来的回报递减。为了克服这一点，我们必须寻找新的计算能力来源，而量子计算机为此提供了一个有希望的解决方案。量子计算机利用了叠加和纠缠等量子现象，这使得加速处理即使是最好的超级计算机也无法在一千年内解决的特定计算问题。量子比特或量子比特是量子计算机的组成部分，用于编码信息，类似于比特在晶体管上的存储方式。类似于晶体管的各种量子比特的物理实现已经被开发出来，例如超导电子电路、原子离子、光粒子和硅中被称为量子点的人造原子。随着单个量子比特的实现现在变得司空见惯，研究的重点正在转移到建立多量子比特系统上。在这个项目中，我们希望使用硅量子点构建一个三乘三的量子比特网格的第一次迭代。这是一个挑战，由于量子比特的脆弱性，量子比特与其周围环境之间的相互作用可能会导致其量子态的丧失。因此，将多个量子比特加在一起将带来一个挑战，即如何减轻它们之间的影响，同时保持对每个量子比特的单独控制，以便它们能够进行量子计算。我们将使用制造传统硅计算机芯片的相同工艺，以便这些量子比特与现有行业兼容，以进行大规模生产。

Computing power has increased exponentially in the last sixty years, all due to the continual improvement of the transistor, the building block of the computer. However, we are now starting to see diminishing returns on advancements in transistor technology. To overcome this, we must look to new sources of computational power, and quantum computers provide a promising solution to this. Quantum computers take advantage of quantum phenomena such as superposition and entanglement, this enables a speed-up for specific computational problems that even the best supercomputers would not be able to solve in a millennium. The quantum bit or qubit, the building block of a quantum computer, is used to encode information similar to how a bit is stored on a transistor. Various physical realisations of qubits, analogous to transistors, have been developed such as superconducting electronic circuits, atomic ions, particles of light and artificial atoms in silicon called quantum dots. With realisations of single qubits now becoming commonplace, research is shifting focus to building systems of multiple qubits. In this project we look to construct the first iteration of a three-by-three grid of qubits using silicon quantum dots. This presents a challenge due to the fragility of qubits, interactions between a qubit and its surrounding environment can lead to the loss of its quantum state. Therefore, adding multiple qubits together will present a challenge in mitigating their influence on one another, while maintaining individual control over each qubit such that they can carry out quantum computations. We will make use of the same processes that are used to make conventional silicon computer chips so that these qubits are compatible with existing industry for mass scale production.