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A magnetic barrier in confined two-dimensional electron gases: Nanomagnetometers and magnetic switches

Michele Governale·Daniel Boese
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Abstract

We investigate the conductance properties of a hybrid ferromagnet-semiconductor structure consisting of a confined two-dimensional electron gas and a transverse ferromagnetic strip on top. Within the framework of the Landauer-Büttiker model, we develop an alternative way to consider magnetic fields. Our method describes devices ranging from a recently realized nanomagnetometer down to quasi one-dimensional quantum wires. We provide a rigorous way to relate the measured resistance to the actual magnetization of the strip. Regarding the quasi one-dimensional wires we propose a new device application, a tunable magnetic switch.

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Michele Governale, Daniel Boese. 2000-09-11. A magnetic barrier in confined two-dimensional electron gases: Nanomagnetometers and magnetic switches. https://doi.org/10.1063/1.1325396

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