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Resistance resonance effects through magnetic edge states
A Nogaret1, S J Bending, M Henini
1Department of Physics, University of Bath, Bath BA2 7AY, UK.
Physical Review Letters
|October 4, 2000
Summary
We observed a sharp resistance resonance in a two-dimensional electron gas due to magnetic edge states formed by a magnetic field gradient. This effect is well-described by a semiclassical drift-diffusion model.
Area of Science:
- Condensed matter physics
- Spintronics
- Mesoscopic physics
Background:
- Two-dimensional electron gases (2DEGs) exhibit unique electronic properties.
- Magnetic field gradients can create novel quantum phenomena.
- Ferromagnetic materials can generate localized magnetic fields.
Purpose of the Study:
- To investigate the magnetoresistance of a 2DEG under an abrupt magnetic field gradient.
- To understand the behavior of magnetic edge states in such a system.
- To model the observed resistance effects.
Main Methods:
- Fabrication of a ferromagnetic stripe on a 2DEG surface.
- Measurement of magnetoresistance as a function of magnetic field.
- Application of a semiclassical drift-diffusion model.
Main Results:
- Observation of a sharp resistance resonance effect at a critical magnetic field B(p).
- Identification of two types of magnetic edge states drifting in opposite directions.
- Successful description of diagonal and off-diagonal resistivity components by the model.
Conclusions:
- The study reveals a novel magnetoresistance resonance in 2DEGs induced by magnetic field gradients.
- Magnetic edge states play a crucial role in the observed phenomena.
- The semiclassical drift-diffusion model effectively captures the magnetic confinement effects.
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