QSense OIST Mini-Symposium Talk 10: "Optically Pumped Magnetometer: Advancements and Perspectives for Biomagnetic Neuroimaging"

Speaker: Prof Tetsuo Kobayashi, Department of Electrical Engineering, Graduate School of Engineering, Kyoto University

Optically Pumped Magnetometer: Advancements and Perspectives for Biomagnetic Neuroimaging
(QSense OIST Mini Symposium Talk 10)​

Optically pumped magnetometer (OPM) is a sensor based on electron-spin polarization of alkali-metal atoms. In recent years, OPMs operating under spin-exchange relaxation-free (SERF) conditions have reached sensitivities comparable to and even surpassing those of superconducting quantum interference devices (SQUIDs). We have been developing the OPMs with pump-probe arrangement since 2006. In 2011, we proposed the first K-Rb spin-exchange hybrid OPM, in which a circularly polarized pump beam and a linearly polarized probe beam crossed orthogonally in a glass cell including vaporized K and Rb atoms together. The homogeneity of the sensing characteristics of the hybrid OPM inside the cell is able to be increased and its sensitivity is also be improved. In 2017, for the first time, we reported that NMR signals and MRI could be acquired with an OPM operating at a Larmor frequency of 5 kHz without the use of any cryogenics. In this presentation, I start with a basic introduction of OPM, followed by a brief history of its development over the past decades and approaches used to improve this sensing technique. I also introduce our recent results of magnetoencephalography (MEG), NMR/MRI measurements using an OPM module to demonstrate its feasibility as an effective sensor for an MEG-MRI fused system having high spatio-temporal resolution towards next generation biomagnetic neuroimaging. We believe that the applicability of compact and affordable biomagnetic neuroimaging systems might provide important advancements in neuroscience and improve the clinical diagnosis of neuropsychiatric disorders as well.

OIST Mini-Symposium for Quantum Sensors of Magnetic and Inertial Forces

This mini-symposium is hosted by the Quantum Machines Unit in the Okinawa Institute of Science and Technology Graduate University, and will take place from Feb 1, 2021 - March 5, 2021. To get the precise schedule and zoom invitation please register below. Attendance is open to any student/faculty member from any of the institutions associated with the speakers.

Summary

Quantum systems are extremely fragile, sensitive to noise and fluctuations by their environments. This, in turn, makes them excellent sensors for a variety of forces and fields. In this mini-symposium we focus on the development of novel quantum sensors which are aimed at the precision sensing of inertial forces such as acceleration or gravity, and magnetic forces.

Such sensors - accelerometers/gravimeters or magnetometers, have a widespread application in industry such as sensing underground water movements using gravimeters, through to magnetic brain imaging using magnetoencephelography. Each week we hear from three international experts on these topics in hour-long seminars and discussions.

For more information, visit the QSense website.