Lau Hoi-Kwan, Plenio Martin B
Institute of Theoretical Physics, Ulm University, Albert-Einstein-Allee 11, 89069 Ulm, Germany.
Phys Rev Lett. 2016 Sep 2;117(10):100501. doi: 10.1103/PhysRevLett.117.100501. Epub 2016 Aug 31.
Implementing a qubit quantum computer in continuous-variable systems conventionally requires the engineering of specific interactions according to the encoding basis states. In this work, we present a unified formalism to conduct universal quantum computation with a fixed set of operations but arbitrary encoding. By storing a qubit in the parity of two or four qumodes, all computing processes can be implemented by basis state preparations, continuous-variable exponential-swap operations, and swap tests. Our formalism inherits the advantages that the quantum information is decoupled from collective noise, and logical qubits with different encodings can be brought to interact without decoding. We also propose a possible implementation of the required operations by using interactions that are available in a variety of continuous-variable systems. Our work separates the "hardware" problem of engineering quantum-computing-universal interactions, from the "software" problem of designing encodings for specific purposes. The development of quantum computer architecture could hence be simplified.
在连续变量系统中实现量子比特量子计算机通常需要根据编码基态设计特定的相互作用。在这项工作中，我们提出了一种统一的形式体系，用于通过一组固定的操作进行通用量子计算，但编码是任意的。通过将一个量子比特存储在两个或四个量子模式的奇偶性中，所有计算过程都可以通过基态制备、连续变量指数交换操作和交换测试来实现。我们的形式体系继承了量子信息与集体噪声解耦的优点，并且具有不同编码的逻辑量子比特可以在不解码的情况下相互作用。我们还提出了一种通过使用各种连续变量系统中可用的相互作用来实现所需操作的可能方案。我们的工作将设计量子计算通用相互作用的“硬件”问题与为特定目的设计编码的“软件”问题分离开来。因此，量子计算机架构的开发可以得到简化。
