1/f noise of a tiny tunnel magnetoresistance sensor originated from a wide distribution of bath correlation time
arXiv:2406.18811 · doi:10.1103/PhysRevApplied.22.014032
Abstract
Tunnel magnetoresistance (TMR) sensor is a highly sensitive magnetic field sensor and is expected to be applied in various fields, such as magnetic recording, industrial sensing, and bio-medical sensing. To improve the detection capability of TMR sensors in low frequency regime it is necessary to suppress the 1/f noise. We theoretically study 1/f noise of a tiny TMR sensor using the macrospin model. Starting from the generalized Langevin equation, 1/f noise power spectrum and the Hooge parameter are derived. The calculated Hooge parameter of a tiny TMR sensor is much smaller than that of a conventional TMR sensor with large junction area. The results provide a new perspective on magnetic 1/f noise and will be useful for improvement of TMR sensors.
8 pages, 3 figures