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arXiv · 0708.1681

Spin valve effect by ballistic transport in ferromagnetic metal (MnAs) / semiconductor (GaAs) hybrid heterostructures

Pham Nam Hai·Yusuke Sakata·Masafumi Yokoyama·Shinobu Ohya·Masaaki Tanaka
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Abstract

We demonstrate the spin valve effect by ballistic transport in fully epitaxial MnAs ferromagnetic metal / GaAs semiconductor / GaAs:MnAs granular hybrid heterostructures. The GaAs:MnAs material contains ferromagnetic MnAs nanoparticles in a GaAs matrix, and acts as a spin injector and a spin detector. Although the barrier height of the GaAs/MnAs interface was found to be very small, relatively large magnetoresistance was observed. This result shows that by using ballistic transport, we can realize a large spin valve effect without inserting a high tunnel barrier at the ferromagnetic metal / semiconductor interface.

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Pham Nam Hai, Yusuke Sakata, Masafumi Yokoyama, Shinobu Ohya, Masaaki Tanaka. 2007-08-13. Spin valve effect by ballistic transport in ferromagnetic metal (MnAs) / semiconductor (GaAs) hybrid heterostructures. https://doi.org/10.1103/physrevb.77.214435

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