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Bistability in a magnetic and nonmagnetic double-quantum-well structure mediated by the magnetic phase transition

Y. G. Semenov·H. Enaya·K. W. Kim
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Abstract

The hole distribution in a double quantum well (QW) structure consisting of a magnetic and a nonmagnetic semiconductor QW is investigated as a function of temperature, the energy shift between the QWs, and other relevant parameters. When the itinerant holes mediate the ferromagnetic ordering, it is shown that a bistable state can be formed through hole redistribution, resulting in a significant change in the properties of the constituting magnetic QW (i.e., the paramagnetic-ferromagnetic transition). The model calculation also indicates a large window in the system parameter space where the bistability is possible. Hence, this structure could form the basis of a stable memory element that may be scaled down to a few hole regime.

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Y. G. Semenov, H. Enaya, K. W. Kim. 2004-12-20. Bistability in a magnetic and nonmagnetic double-quantum-well structure mediated by the magnetic phase transition. https://doi.org/10.1063/1.1864237

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