The characteristic analysis of the built-in vector atomic magnetometer in a nuclear magnetic resonance oscillator

Qiyuan Jiang,Jiajia Li,Zhiguo Wang,Hui Luo,Yi Zhang

doi:10.1063/1.5082152

Abstract

We analyze the amplitude-frequency, phase-frequency, signal amplification, linear range, and vector characteristics of the built-in vector atomic magnetometer operating at extreme off-resonance condition in a nuclear magnetic resonance oscillator, which makes possible its performance improvement by a balanced strategy in optimizing the parameters based on the proposed model. The experiment validates our prediction of the amplitude-frequency characteristic, and the numerical simulation indicates that the applied carrier field with following demodulation procedure holds the potential to give one order of magnitude, which is experimentally-validated to have at least twice, signal enhancement and enable the vector characteristic, where a large longitudinal static field and an appropriate transverse relaxation time are preferred to have optimized characteristics depending on different applications.

Highlights

High performance nuclear magnetic resonance (NMR) oscillators benefit various applications such as the magnetic resonance imaging (MRI),1–3 the NMR spectroscopy,4–7 and the NMR gyroscope.8–11 The Larmor precession frequency of the detected nuclear species is utilized to enable the signal detection of the NMR oscillator, which is further achieved by measuring nuclear spins with the built-in magnetometer.12The arguably most mature set-ups are the atomic magnetometers13–15 and the superconducting quantum interference devices (SQUID) magnetometers,16,17 yet the miniaturized atomic magnetometers facilitating ultra-sensitive detection of magnetic field with no needs of cryogenic condition, are more promising than SQUID magnetometers for the application of the built-in magnetometer in the NMR oscillator
We make characteristic analysis of the built-in vector atomic magnetometer (VAM) in the NMR oscillator, including electron paramagnetic resonance (EPR) amplitude-frequency, EPR phase-frequency, signal amplification by the carrier field, linear range, and vector characteristics, where the magnetometer mainly operates at its extreme off-resonance condition, to enable the performance improvement by optimizing the corresponding parameters and facilitate its application in the NMR oscillator
The schematic experimental set-up of the built-in VAM as well as the NMR oscillator is shown in Fig. 1, where a vapor cell filled with condensed Rubidium atoms (87Rb, which has γ = 2π × 6998[rad/(s⋅μT)]), and buffer gases consisting of 300 Torr N2 as quencher, was placed in the center

Summary

Introduction

The Larmor precession frequency of the detected nuclear species is utilized to enable the signal detection of the NMR oscillator, which is further achieved by measuring nuclear spins with the built-in magnetometer.. The arguably most mature set-ups are the atomic magnetometers and the superconducting quantum interference devices (SQUID) magnetometers, yet the miniaturized atomic magnetometers facilitating ultra-sensitive detection of magnetic field with no needs of cryogenic condition, are more promising than SQUID magnetometers for the application of the built-in magnetometer in the NMR oscillator. The vector atomic magnetometer (VAM) is especially preferred as the built-in magnetometer which enables the compensation of the stray magnetic field along multiple axes in the NMR oscillator.. Understanding the characteristics of the built-in VAM is crucial in the NMR oscillator. The vector atomic magnetometer (VAM) is especially preferred as the built-in magnetometer which enables the compensation of the stray magnetic field along multiple axes in the NMR oscillator. understanding the characteristics of the built-in VAM is crucial in the NMR oscillator.

Methods

Results

Conclusion