Patent ID: 8368396
Filing Date: 2013-02-05
Classification: G01R

Abstract:
1. A magnetic sensor element comprising a multi-magnetic domain structure in which a plurality of magnetic domains extend in a row in one direction and in which the magnetic domains that are adjoining have easy magnetization axes in opposite directions to each other, wherein: the multi-magnetic domain structure has a surface region, and within the surface region, when counting from one end of the multi-magnetic domain structure, affinities for a magnetic particle or a substance to be immobilized on the magnetic particle are mutually different at first surface portions located at a boundary between a (2n−1)th (n being a natural number) magnetic domain and a (2n)th magnetic domain and second surface portions located at a boundary between the (2n)th magnetic domain and a (2n+1)th magnetic domain and wherein the affinities of any of the first surface portions are higher or lower than the affinities of any of the second surface portions.