报告题目：Subnanotesla, shield-less, field-compensation-free, wave-mixing-enhanced body-temperature atomic magnetometry for biomagnetism

报 告 人：Lu Deng, Senior physicist, National Institute of Standards and Technology

报告时间：2018-05-28 13:30

报告地点：理科楼C302报告厅

报告摘要：Human nervous system activities produce extremely weak transient magnetic fields at nano-Tesla (nT) to pico-Tesla (pT) levels during the exchange of information. The ability to study these dynamic bio-magnetic impulses in situ under ambient conditions would therefore provide unique insight into real-time physiological processes. We report an optical inelastic-wave-mixing-enhanced atomic magnetometry technique that results in sub-nT magnetic field detection at temperatures compatible with the human body without magnetic field shielding, zero-field compensation, or RF-modulation/high-frequency phase-locking spectroscopy. Using Gaussian magnetic pulses that mimic the transient magnetic fields created by an action potential on a frog’s nerve, we demonstrate more than 300,000-fold enhancement of magneto-optical rotation signal power spectral density （>550-fold signal amplitude SNR enhancement) over the conventional single-beam Λ？scheme atomic magnetometry method. This new technique may bring possibilities for extremely sensitive magnetic field imaging of any biological systems accessible via an optical fiber (endoscopic) in clinical environments.