Quantum sensor noise suppression methods for measuring weak currents
量子传感器在微弱电流检测中的噪声抑制方法

摘要

量子传感器用于微弱电流检测时，热噪声、散粒噪声及量子退相干噪声干扰严重影响检测精度。热噪声源于粒子热运动，与温度相关；散粒噪声由电荷离散性导致；量子退相干噪声则因量子比特与环境相互作用产生。针对这些噪声，低温冷却、高品质材料选用可降低热噪声，优化量子比特设计结合电流整形技术能抑制散粒噪声，量子纠错码与主动反馈控制可应对量子退相干噪声。多维度综合优化策略从材料、电路设计、系统层面协同作用，通过噪声功率谱密度、检测精度及稳定性测试评估噪声抑制效果，为实现高精度微弱电流检测提供有效路径。

Abstract

When quantum sensors are used to measure weak currents, thermal noise, shot noise, and quantum decoherence noise significantly affect the accuracy of the measurements. Thermal noise, which is temperature-dependent, originates from the thermal motion of particles; shot noise is caused by the discreteness of charges; and quantum decoherence noise arises from the interaction between qubits and the environment. To address these issues, low-temperature cooling and the use of high-quality materials can reduce thermal noise. Optimizing qubit design and incorporating current shaping techniques can help suppress shot noise. Quantum error correction codes and active feedback control can effectively manage quantum decoherence noise. A multi-dimensional optimization strategy, involving material selection, circuit design, and system integration, evaluates the effectiveness of noise suppression through tests on noise power spectral density, measurement accuracy, and stability, providing an effective approach to achieve high-precision weak current detection.