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  • Micron-Scale Anomalous Hall Sensors Based on FexPt1−x Thin Films with a Large Hall Angle and near the Spin-Reorientation Transition
Title: Micron-Scale Anomalous Hall Sensors Based on FexPt1−x Thin Films with a Large Hall Angle and near the Spin-Reorientation Transition
In this work, we fabricate and characterize an energy-efficient anomalous Hall sensor based on soft-magnetic FexPt1−x thin films with a large anomalous Hall angle. By varying the composition of the FexPt1−x alloy, its layer thickness and interfacial materials, the magnetization is tuned to be near the spin transition between the perpendicular and in-plane reorientations. We performed magneto-transport and noise characterizations on anomalous Hall sensors with a small sensing area of 20 × 20 µm2 in the 180 to 350 K temperature range. We found the best performance in a 1.25-nm-thick Fe0.48Pt0.52 sandwiched by two 1.6-nm-thick MgO layers at room temperature. The sensor has a large anomalous Hall angle of 1.95%. Moreover, it has the best field detectability of 237.5 nT/√Hz at 1 Hz and 15.3 nT/√Hz at 10 kHz, as well as a high dynamic reserve of 112.0 dB. These results suggest that the FexPt1−x alloy system is suitable for energy-efficient anomalous Hall sensors, particularly in micro-sensing applications.  more » « less
Award ID(s):
1936221
PAR ID:
10300463
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Nanomaterials
Volume:
11
Issue:
4
ISSN:
2079-4991
Page Range / eLocation ID:
854
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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