In:
Journal of Applied Physics, AIP Publishing, Vol. 129, No. 2 ( 2021-01-14)
Abstract:
Magnetic tunnel junctions (MTJs) have been identified as promising candidates for the development of high-performance, ultra-low field magnetometers due to their high sensitivity, low cost, low power consumption, and small size. However, 1/f noise is often quite large at low frequencies and inevitably becomes one of the most difficult issues in developing a magnetic field sensor with ultrahigh sensitivity. Low-frequency 1/f noise can have both electric and magnetic origins, and it is a result of complex non-linear interactions between many degrees of freedom inside a sensor. Therefore, a reduction of the 1/f noise can be expected for the magnetic sensor with very small dimensions. Here, the dependence of the 1/f noise on voltage and strong hard-axis bias field in deep submicrometer-sized MgO-based MTJs is investigated with various junction sizes. The noise spectra were measured by using a home-built low-frequency noise measurement setup with maximum frequency up to 30 kHz. We find that the noise spectral power density is 1/f-like at low frequencies. The experimental results suggest a relative reduction of 1/f noise with respect to the intrinsic thermal noise in small-sized MTJs. The results may open a new approach for reducing the 1/f noise level in MTJ nanosensors.
Type of Medium:
Online Resource
ISSN:
0021-8979
,
1089-7550
Language:
English
Publisher:
AIP Publishing
Publication Date:
2021
detail.hit.zdb_id:
220641-9
detail.hit.zdb_id:
3112-4
detail.hit.zdb_id:
1476463-5