单比特量子逻辑门是实现量子计算的核心元件,其高保真度和良好的鲁棒性是不可或缺的关键特性.利用几何相位的全局特性来设计量子门是一个重要的方法,该方法能够较好地抵抗某些局部干扰,从而提高门操作的容错能力.在一些实验方案中,常在量子门操作之后施加一个补偿脉冲以提高保真度.在非绝热几何量子计算的框架下,从一般的含时微扰论出发,考察了系统误差对保真度的影响,并得出了相应的解析结果.此外,还通过数值模拟验证了这些解析结果对量子门鲁棒性的影响,为设计更优的脉冲确立了可能的方向.研究结果表明,加入补偿脉冲后,量子非门和S门保真度的偏差可以降低约50%.
Single qubit gates are the core components for realizing quantum computing, and their high fidelity and robustness are indispensable key characteristics. Designing quantum gates using the global properties of geometric phases is an important approach, as this method can effectively resist certain local perturbations, thereby improving the fault tolerance of gate operations. In some experimental schemes, a compensation pulse is often applied after quantum gate operations to enhance fidelity. Within the framework of non-adiabatic geometric quantum computing and based on the general theory of time-dependent perturbation, this paper examined the impact of system errors on fidelity and derived the corresponding analytical results. Moreover, the paper validated these analytical results through numerical simulations, demonstrating their influence on the robustness of quantum gates. This provides a potential direction for designing more optimal pulses. The results show that the fidelity error of the NOT gate and S gate can be reduced by about 50% with the help of a compensation pulse.
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