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Semitransparent anisotropic and spin Hall magnetoresistance sensor enabled by spin-orbit toque biasing

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 نشر من قبل Yumeng Yang
 تاريخ النشر 2017
  مجال البحث فيزياء
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We demonstrate an ultrathin and semitransparent anisotropic and spin Hall magnetoresistance sensor based on NiFe/Pt heterostructure. The use of spin-orbit torque effective field for transverse biasing allows to reduce the total thickness of the sensors down to 3 - 4 nm and thereby leading to the semitransparency. Despite the extremely simple design, the spin-orbit torque effective field biased NiFe/Pt sensor exhibits level of linearity and sensitivity comparable to those of sensors using more complex linearization schemes. In a proof-of-concept design using a full Wheatstone bridge comprising of four sensing elements, we obtained a sensitivity up to 202.9 m{Omega}/Oe, linearity error below 5%, and a detection limit down to 20 nT. The transmittance of the sensor is over 50% in the visible range.

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