Wheatstone bridge sensor composed of linear MgO magnetic tunnel junctions

A full Wheatstone bridge sensor composed of linear MgO based magnetic tunnel junctions(MTJ) was designed and achieved. The magnetization direction of reference layers in the required bridge arms was successfully switched by using local current heating method, also demonstrating a viable method of manipulation of pinning direction for exchange bias system on a chip level. The final bridge output shows approximately full signal of individual MTJ but almost null output in the absence of any applied sensing field and small offset of voltage and field.

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