Quantum error mitigation (QEM) is a class of promising techniques capable of reducing the computational error of variational quantum algorithms tailored for current noisy intermediate-scale quantum computers. The recently proposed permutation-based methods are practically attractive, since they do not rely on any a priori information concerning the quantum channels. In this treatise, we propose a general framework termed as permutation filters, which includes the existing permutation-based methods as special cases. In particular, we show that the proposed filter design algorithm always converge to the global optimum, and that the optimal filters can provide substantial improvements over the existing permutation-based methods in the presence of narrowband quantum noise, corresponding to large-depth, high-error-rate quantum circuits.

翻译：量子误差缓解(QEM)是一类有希望的技术,能够减少为当前噪音居中量级计算机定制的变异量算法的计算错误。 最近提出的基于变异性计算法在实际上很有吸引力,因为它们并不依赖于量子信道的任何先验信息。在这个论题中,我们提议了一个称为变异过滤器的一般框架,其中包括现有的基于变异性的方法,作为特殊情况。特别是,我们表明,拟议的过滤设计法总是与全球最佳方法趋同,而最佳过滤法在存在窄带量子噪声的情况下,可以大大改进现有基于变异性计算法,这与大型、高eror-速率的量子电路相对应。