A Resonant Lorentz-Force Magnetometer Featuring Slotted Double-Ended Tuning Fork Capable of Operating in a Bias Magnetic Field

TY - JOUR

T1 - A Resonant Lorentz-Force Magnetometer Featuring Slotted Double-Ended Tuning Fork Capable of Operating in a Bias Magnetic Field

AU - Wang, Yuan

AU - Song, Xiaoxiao

AU - Li, Fangzheng

AU - Gao, Lu

AU - Li, Chengxin

AU - Xi, Jingqian

AU - Liu, Huafeng

AU - Zhao, Chun

AU - Wang, Chen

AU - Tu, Liang Cheng

AU - Kraft, Michael

N1 - Funding Information: This work was supported by the National Key Research and Development Program of China under Grant 2018YFB2002300. This paper is an extended work based on "A Resonant Lorentz-Force Magnetometer Based on Cavity Slotted Double-End Tuning Fork to Enhance Q-Factor and Sensitivity," from the Transducers 2021 Conference [DOI: 10.1109/Transducers50396.2021.9495528]. Publisher Copyright: © 1992-2012 IEEE.

PY - 2021/9/29

Y1 - 2021/9/29

N2 - Magnetometers are ubiquitous in applications covering many aspects of modern life, such as navigation, smart devices, biomedical systems, geological surveying and aerospace. This work reports a resonant Lorentz-force magnetometer featuring structural topology, in which cavity slots are incorporated in the device structure to improve the thermoelastic dissipation. Such a device is capable of sensing a small Lorentz-force and can be used as a sensitive magnetic field sensor. The most prominent property of this subject is implementing sensing tasks under a large bias magnetic field. The proposed magnetometer achieves a quality factor of 43000 in a vacuum of 4 mPa, a Lorentz-force sensitivity of 0.2 Hz/nN, and a magnetic field change sensitivity of 3375 Hz/T. The topology of the double-ended tuning fork (DETF) using cavity slots in the tine beams resulted in a 5.9-fold enhancement of the Q-factor compared to a common DETF resonator with the same geometry. Experimental characterization of the proposed magnetometer confirms its feasibility and functionality. Experiments about an application scenario with a large pre-existing bias magnetic field were carried out. The prototype device demonstrated a magnetic field change sensitivity of 2585 Hz/T and a noise-limited resolution of 210 nT/ surd Hz, under a bias magnetic field of 0.13 T.

AB - Magnetometers are ubiquitous in applications covering many aspects of modern life, such as navigation, smart devices, biomedical systems, geological surveying and aerospace. This work reports a resonant Lorentz-force magnetometer featuring structural topology, in which cavity slots are incorporated in the device structure to improve the thermoelastic dissipation. Such a device is capable of sensing a small Lorentz-force and can be used as a sensitive magnetic field sensor. The most prominent property of this subject is implementing sensing tasks under a large bias magnetic field. The proposed magnetometer achieves a quality factor of 43000 in a vacuum of 4 mPa, a Lorentz-force sensitivity of 0.2 Hz/nN, and a magnetic field change sensitivity of 3375 Hz/T. The topology of the double-ended tuning fork (DETF) using cavity slots in the tine beams resulted in a 5.9-fold enhancement of the Q-factor compared to a common DETF resonator with the same geometry. Experimental characterization of the proposed magnetometer confirms its feasibility and functionality. Experiments about an application scenario with a large pre-existing bias magnetic field were carried out. The prototype device demonstrated a magnetic field change sensitivity of 2585 Hz/T and a noise-limited resolution of 210 nT/ surd Hz, under a bias magnetic field of 0.13 T.

KW - double-ended tuning fork

KW - Lorentz-Force

KW - Magnetometer

KW - Q-factor

UR - http://www.scopus.com/inward/record.url?scp=85116889417&partnerID=8YFLogxK

U2 - 10.1109/JMEMS.2021.3113769

DO - 10.1109/JMEMS.2021.3113769

M3 - Article

AN - SCOPUS:85116889417

SN - 1057-7157

VL - 30

SP - 958

EP - 967

JO - Journal of Microelectromechanical Systems

JF - Journal of Microelectromechanical Systems

IS - 6

ER -