Subnanotesla, shield-less, field-compensation-free, wave-mixing-enhanced body-temperature atomic magnetometry for biomagnetism
报告题目: Subnanotesla, shield-less, field-compensation-free, wave-mixing-enhanced body-temperature atomic magnetometry for biomagnetism
报 告 人: Lu DENG
Human nervous system activities produce extremely weak transientmagnetic fields at nano-Tesla (nT) to pico-Tesla (pT) levels during the exchange of information. The ability to study these dynamic bio-magnetic impulsesin 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.
Dr. Lu Deng received his BS degree in theoretical particle physics from USTC in China in 1982 and Ph.D. in nuclear physics and optical physics in 1989 from Baylor University in 1989 under a full scholarship. He was a Petroleum Research Fund Fellow (University of California, Davis) from 1989-1991 and US Department of Energy ORAU/ORIES Fellow (US DOE Oak Ridge National Laboratory) in early and mid 1990s'. He worked with two 1997 Nobel Laureates Prof. Steven Chu (in 1990, Stanford University) and Dr. William Phillips (1997-2000, NIST). He joined NIST in 1996 and has co-authored more than 125 research papers in the past 24 years including 3 in Science, 1 in Nature (cover illustration), 2 in SCIENCE ADVANCES (equivalent to Nature Physics and／or Nature Communications) and more than 20 in PRL. He was instrumental in developing NIST's first sodium BEC and has contributed significantly to the first rubidium BEC setup in China. He has been actively contributing to the cold atom physics community in China since 1999. Dr. Deng is a recipient of OSA 2002 Archie Machan Prize. He received US Department of Commerce and NIST 2002 E.U. Condon Award for his contribution to BEC research. Recent most notable ground breaking research include discovery of a new nonlinear optical crystal thought to not exist under ambient conditions (SCIENCE ADVANCES), matter-wave induced optical wave transparency (PRL Editors' suggestion), novel nonlinear optical atomic magnetometry technology (SCIENCE ADVANCES). Since 2009 he pioneered a new research field in cold atom physics, i.e., Nonlinear Optics with Quantum Gases, that opens a new chapter to the matured field of nonlinear and quantum optics.