标题： 通过连续动力学解耦保护$\sqrt{SWAP}$操作免受通用误差和残差误差的影响 显示英文标题

标题： Protecting the $\sqrt{SWAP}$ operation from general and residual errors by continuous dynamical decoupling

摘要： 我们研究了在退相干条件下，一个连续解耦的两比特量子态在执行$\sqrt{SWAP}$量子操作时出现的错误。 我们考虑了一种基于海森堡交换相互作用实现该量子门的方法，这种方法本身足以实现通用量子计算。 此外，我们引入了一种与海森堡哈密顿量对易的连续动力学解耦方案，以保护量子门免受系统-环境相互作用引起的振幅阻尼和去相位误差的影响。 我们考虑了两种错误保护设置。 一种保护量子比特免受振幅阻尼和去相位误差的影响。 另一种将振幅阻尼作为残余误差，并仅保护量子比特免受去相位误差的影响。 在两种设置下，我们分别研究了量子比特与公共环境和独立环境的相互作用。 我们研究了不同环境谱密度下错误对纠缠和保真度的影响。 显示英文摘要

摘要： We study the occurrence of errors in a continuously decoupled two-qubit state during a $\sqrt{SWAP}$ quantum operation under decoherence. We consider a realization of this quantum gate based on the Heisenberg exchange interaction, which alone suffices for achieving universal quantum computation. Furthermore, we introduce a continuous-dynamical-decoupling scheme that commutes with the Heisenberg Hamiltonian to protect it from the amplitude damping and dephasing errors caused by the system-environment interaction. We consider two error-protection settings. One protects the qubits from both amplitude damping and dephasing errors. The other features the amplitude damping as a residual error and protects the qubits from dephasing errors only. In both settings, we investigate the interaction of qubits with common and independent environments separately. We study how errors affect the entanglement and fidelity for different environmental spectral densities.