Quantum computing with LDPC codes

使用 LDPC 码进行量子计算

• 批准号: 2107667
• 金额: --
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2107667
• 关键词: Quantum; computing; LDPC; codes

Errors in quantum computers are unavoidable. Controlling quantum bits (qubits)stored in individual electrons or photons is significantly more challenging thancontrolling bits in traditional computers. Direct use of physical qubits typicallyonly yields very short lifetimes such that information is lost before anymeaningful computation can be executed. Fortunately, we can use quantumerror correcting codes to make a logical qubit that is protected against errors.This approach allows us to extend the lifetime as long as is needed to completea computation. Although, the longer we extend the lifetime the more physicalqubits will be needed per logical qubit. Maybe hundreds or thousands of physicalqubits will be needed per logical qubit. Current quantum hardware supportsfewer than 50 qubits so this cost is substantial. Therefore, a fundamentalrethinking of how we design quantum computers is a pressing near-future issue.The most efficient codes in conventional information technology systems arecalled low-density parity check codes and are used in all Wi-Fi networks andmobile communication networks. This theoretical PhD project will explore thedifferent ways that these highly efficient classical techniques can be convertedinto highly efficient quantum codes.

量子计算机中的错误是不可避免的。在传统计算机中，控制在单个电子或光子中存储的量子位（Qubits）比控制位更具挑战性。直接使用物理量子位通常会产生很短的寿命，因此在执行任何含义的计算之前会丢失信息。幸运的是，我们可以使用QuantumError校正代码来制作一个逻辑量子，以防止错误。此方法使我们能够在完成计算的需要时延长寿命。虽然，我们延长寿命的时间越长，在逻辑量子的情况下，需要更多的物理问题。在逻辑量子的情况下，可能需要数百或数千个物理问题。当前的量子硬件支持者超过50 QUAT，因此这一成本很大。因此，对我们如何设计量子计算机的基本思维是一个紧迫的近乎未来问题。传统信息技术系统中最有效的代码均为低密度奇偶校验校验代码，并用于所有Wi-Fi网络和摩托车通信网络中。这个理论博士学位项目将探讨这些高效的经典技术可以转换为高效量子代码的方式。