The 81st JSAP Autumn Meeting, 2020

Presentation information

Oral presentation

10 Spintronics and Magnetics » 10.3 Spin devices, magnetic memories and storages

[10p-Z08-11~17] 10.3 Spin devices, magnetic memories and storages

Thu. Sep 10, 2020 4:00 PM - 6:00 PM Z08

Satoshi Iihama(Tohoku Univ.)

5:30 PM - 5:45 PM

[10p-Z08-16] Development of highly sensitive and low noise TMR magnetic sensor for bio-magnetic field measurement

Kousuke Fujiwara1, Mikihiko Oogane2, Sabri Cakir1, Seiji Kumagai1, Tadashi Arimoto3, Yasuo Ando1,2 (1.Spin Sensing Factory Corp., 2.Tohoku Univ., 3.KONICA MINOLTA, INC.)

Keywords:magnetic sensor, bio magnetic field, magnetocardiography

We have developed TMR sensor with magnetic resolution of 7 pT/√Hz @ 1 Hz. In the magnetocardiography measurement, an R peak due to the heartbeat was observed, and a clear QRS peaks was observed by averaging. We also succeeded in reducing the magnetic noise to about half by using the free layer that was magneto-statically coupled. Furthermore, we succeeded in dramatically reducing environmental noise by preparing a gradiometer with a sensor close to the signal source and a sensor far from the signal, and demonstrated the feasibility of a highly sensitive magnetic sensor that does not require a magnetic shielded room.