抄録
Currently, SQUID is the most sensitive of the magnetic sensor and is used for the measurement of biological fields. However, dissemination of the device to the medical field realistically is very strict due to the big size of the device, in terms of introduction and maintenance costs. In particular, a dewar for holding a low temperature is required in order to immersion in liquid helium for operating the SQUID element. The distance of the dewar from the head surface, and also the dewar surface from the SQUID element, act as restraint for accurate measurement. This paper proposes a sensor for the biomagnetic field measurement with magnetic tunnel junction (MTJ) devices. It can be operated at room temperature and is brought it into close contact with the head. We describe the necessary technical challenges toward its realization and the feasibility in the future.