Magnetic microscopic imaging with an optically pumped magnetometer and flux guides

Journal Article · Sun Jan 22 23:00:00 EST 2017 · Applied Physics Letters

DOI: https://doi.org/10.1063/1.4975069 · OSTI ID:1344366

Kim, Young Jin  ^[1]; Savukov, Igor Mykhaylovich  ^[1]; Huang, Jen -Huang ^[2]; Nath, Pulak  ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); National Tsing Hua Univ., Hsinchu (Taiwan)

Here, by combining an optically pumped magnetometer (OPM) with flux guides (FGs) and by installing a sample platform on automated translation stages, we have implemented an ultra-sensitive FG-OPM scanning magnetic imaging system that is capable of detecting magnetic fields of ~20 pT with spatial resolution better than 300 μm (expected to reach ~10 pT sensitivity and ~100 μm spatial resolution with optimized FGs). As a demonstration of one possible application of the FG-OPM device, we conducted magnetic imaging of micron-size magnetic particles. Magnetic imaging of such particles, including nano-particles and clusters, is very important for many fields, especially for medical cancer diagnostics and biophysics applications. For rapid, precise magnetic imaging, we constructed an automatic scanning system, which holds and moves a target sample containing magnetic particles at a given stand-off distance from the FG tips. We show that the device was able to produce clear microscopic magnetic images of 10 μm-size magnetic particles. In addition, we also numerically investigated how the magnetic flux from a target sample at a given stand-off distance is transmitted to the OPM vapor cell.

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: LDRD; USDOE
• Grant/Contract Number: AC52-06NA25396
• OSTI ID: 1344366
• Report Number(s): LA-UR-16-28672
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 4 Vol. 110; ISSN 0003-6951
• Publisher: American Institute of Physics (AIP)Copyright Statement
• Country of Publication: United States
• Language: English