Nuclear quadrupole resonance spectroscopy with a femtotesla diamond magnetometer.
Yaser SilaniJanis SmitsIlja FescenkoMichael W MaloneAndrew F McDowellAndrey JarmolaPauli KehayiasBryan A RichardsNazanin MosavianNathaniel RistoffVictor M AcostaPublished in: Science advances (2023)
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 is T 2 *=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.
Keyphrases
- mass spectrometry
- room temperature
- energy transfer
- high resolution
- high frequency
- liquid chromatography
- nitric oxide
- high performance liquid chromatography
- tandem mass spectrometry
- gas chromatography
- public health
- simultaneous determination
- healthcare
- multiple sclerosis
- global health
- photodynamic therapy
- functional connectivity
- fluorescence imaging