论文标题
量子位的最佳熵压缩和纯化
Optimal Entropy Compression and Purification in Quantum Bits
论文作者
论文摘要
全局统一转换（OPTSWAPS）最佳地增加了量子系统中任何混合计算量子争夺量的偏差（以对角度密度矩阵表示），向特定的计算基础状态呈现，实际上会提高其纯度。描述了通过实施上述数据压缩技术（以前使用的3B-comp的概括）来实现这一目标的量子电路。这些电路通过将其von Neumann或Shannon熵的一部分转移到任何数量的周围码头中，从而使计算量子保持纯度增量，并且对最初偏见的完整范围有效。使用OPTSWAPS，一种可行的新方法，算法可以在开放到热水池的工程量子寄存器中实现量子标准量的层次依赖性冷却。除了满足某些架构中Divincenzo量子计算的两个标准外，还讨论了这项工作对量子数据压缩和量子热力学的含义。
Global unitary transformations (OPTSWAPS) that optimally increase the bias of any mixed computation qubit in a quantum system -- represented by a diagonal density matrix -- towards a particular state of the computational basis which, in effect, increases its purity are presented. Quantum circuits that achieve this by implementing the above data compression technique -- a generalization of the 3B-Comp used before -- are described. These circuits enable purity increment in the computation qubit by maximally transferring part of its von Neumann or Shannon entropy to any number of surrounding qubits and are valid for the complete range of initial biases. Using the optswaps, a practicable new method that algorithmically achieves hierarchy-dependent cooling of qubits to their respective limits in an engineered quantum register opened to the heat-bath is delineated. In addition to multi-qubit purification and satisfying two of DiVincenzo's criteria for quantum computation in some architectures, the implications of this work for quantum data compression and quantum thermodynamics are discussed.
