High magnetic moment particle detection

摘要

A device includes a sensor surface and a pair of electrodes. The sensor surface includes a first conductive layer separated from a second conductive layer by an intermediary layer, a magnetization direction of the first conductive layer and a magnetization direction of the second conductive layer having a ground state orientation of approximately 0 degrees. An electrical resistance between the pair of electrodes is determined by a magnetic field proximate the sensor surface.

主权项

1. A device comprising:
a sensor having a surface, the surface including a plurality of conductive layers interspersed by a plurality of intermediary layers, a magnetization direction of a first subset of the plurality of conductive layers and a magnetization direction of a second subset of the plurality of conductive layers having a ground state orientation of approximately 0 degrees, wherein the first subset is exclusive of the second subset; and a pair of electrodes coupled to the sensor surface and wherein an electrical resistance difference between the pair of electrodes is determined by a magnetic field proximate the sensor surface and wherein the sensor surface has an aspect ratio, corresponding to a length and a width of the sensor surface, that is sufficiently small such that a magnetic dipole field of a nanoparticle proximate the sensor surface is detectable as an electrical resistance difference between the pair of electrodes.