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Title: Nuclear quadrupole resonance spectroscopy with a femtotesla diamond magnetometer
Radio frequency (RF) magnetometers based on nitrogen vacancy centers in diamond are predicted to offer femtotesla sensitivity, but previous experiments were limited to the picotesla level. We demonstrate a femtotesla RF magnetometer using a diamond membrane inserted between ferrite flux concentrators. The device provides ~300-fold amplitude enhancement for RF magnetic fields from 70 kHz to 3.6 MHz, and the sensitivity reaches ~70 fT√s at 0.35 MHz. The sensor detected the 3.6-MHz nuclear quadrupole resonance (NQR) of room-temperature sodium nitrite powder. The sensor’s recovery time after an RF pulse is ~35 μs, limited by the excitation coil’s ring-down time. The sodium-nitrite NQR frequency shifts with temperature as −1.00±0.02 kHz/K, the magnetization dephasing time isT2*=887±51 μs, and multipulse sequences extend the signal lifetime to 332±23 ms, all consistent with coil-based studies. Our results expand the sensitivity frontier of diamond magnetometers to the femtotesla range, with potential applications in security, medical imaging, and materials science.  more » « less
Award ID(s):
1945148
PAR ID:
10497387
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAAS Science Advances
Date Published:
Journal Name:
Science Advances
Volume:
9
Issue:
24
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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