Download all files (1.38 MB)

Collection

Citation

Description:

Suppression of 1/f noise in tunnel magnetoresistance (TMR) sensors is a central issue in the realization of magnetic field sensors with ultrafine magnetic field detectivity. Although AC modulation with an external magnetic field has been proposed as a method to shift the operating frequency of a sensor to a high frequency and substantially suppress 1/f noise, its effects on the two types of 1/f noise, that is, magnetic and electrical 1/f noise, are not well understood. In this study, we investigated the noise characteristics and signal detection performance of TMR sensors with an even-function resistance-magnetic field curve operated by the AC modulation method. For one TMR device in which the magnetic 1/f noise was dominant, AC modulation degraded the magnetic field detectivity owing to the additional noise induced by the AC modulation field. However, in another TMR device, in which the electrical 1/f noise was artificially enhanced by introducing lattice defects in the MgO tunnel barrier, AC modulation effectively suppressed the 1/f noise and improved the magnetic field detectivity by one order. This demonstrates that the AC modulation method using an external magnetic field is effective for magnetic field sensors in which electrical 1/f noise is dominant.

Rights:

• In Copyright
  

  This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article
  appeared in Tomoya Nakatani. Appl. Phys. 134, 213904 (2023) and
  may be found at https://doi.org/10.1063/5.0180812

Keyword: tunnel magnetoresistance, magnetic sensor, noise, 1/f noise

Date published: 2023-12-07

Publisher: AIP Publishing

Journal:

• JOURNAL OF APPLIED PHYSICS (ISSN: 00218979) vol. 134 issue. 21 p. 213904-213904

Funding:

• 日本学術振興会 20K04588 (科研費基盤研究(C))

Manuscript type: Author's version (Accepted manuscript)

MDR DOI: https://doi.org/10.48505/nims.4364

First published URL: https://doi.org/10.1063/5.0180812

Related item:

Other identifier(s):

Contact agent:

Updated at: 2024-02-16 12:27:44 +0900

Published on MDR: 2024-01-23 16:30:11 +0900