论文标题
低频量子传感
Low-frequency quantum sensing
论文作者
论文摘要
精致的灵敏度是量子传感器的显着优势。拉姆西序列允许精确测量直接电流场，而类似Hahn-Echo的序列测量交替的电流场。但是，由于有限的连贯性时间，后者被限制在高频场（高于$ 1 $ kHz）的情况下使用，因此在低频范围内留下了较不敏感的非相关方法。在本文中，我们建议用基于拟合的算法桥接缝隙，具有频率无关的灵敏度，以相干测量低频场。由于算法从基于连贯的测量中受益，因此其单个氮存道中心的演示符合$ 9.4 $ NT Hz $^{ - 0.5} $的灵敏度，低于$ 0.6 $ kHz的频率下降到近稳定场。为了在各种情况下检查潜力，我们将算法应用于数十NTS的背景字段，并通过同步测量低频信号。
Exquisite sensitivities are a prominent advantage of quantum sensors. Ramsey sequences allow precise measurement of direct current fields, while Hahn-echo-like sequences measure alternating current fields. However, the latter are restrained for use with high-frequency fields (above approximately $1$ kHz) due to finite coherence times, leaving less-sensitive noncoherent methods for the low-frequency range. In this paper, we propose to bridge the gap with a fitting-based algorithm with a frequency-independent sensitivity to coherently measure low-frequency fields. As the algorithm benefits from coherence-based measurements, its demonstration with a single nitrogen-vacancy center gives a sensitivity of $9.4$ nT Hz$^{-0.5}$ for frequencies below about $0.6$ kHz down to near-constant fields. To inspect the potential in various scenarios, we apply the algorithm at a background field of tens of nTs, and we measure low-frequency signals via synchronization.
