Measurement errors limit the performance of near-term quantum computers and their potential for practical application. However they are partly correctable after a calibration step that requires, for a complete implementation on a register of n qubits, 2 ⁿ additional measurements. Here we introduce an approximate but efficient method for multiqubit measurement error characterization and mitigation requiring the classical processing of 2 ⁿ 2 ⁿ matrices, but only O(4 ^k n ²) measurements, where k = O(1) is the number of qubits in a correlation volume. We demonstrate and validate the method on an IBM Q processor with registers of 4 and 8 superconducting qubits.

测量误差限制了近期量子计算机的性能及其在实际应用中的潜力。但是，在一个校准步骤之后，它们在某种程度上是可校正的，而要在n个量子位的寄存器上完全实施，则需要2 ^n次附加测量。在这里，我们介绍了一种近似但有效的方法，用于多量子位测量误差的表征和缓解，该方法需要对2 ⁿ 2 ^n个矩阵进行经典处理，但仅进行O（4 ^k n ²）个测量，其中k = O （1）是相关卷中的qubit数。我们在具有4个超导量子位和8个超导量子位的寄存器的IBM Q处理器上演示并验证了该方法。