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Quantum and semiclassical study of magnetic anti-dots

B. Kocsis·G. Palla·J. Cserti
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Abstract

We study the energy level structure of two-dimensional charged particles in inhomogeneous magnetic fields. In particular, for magnetic anti-dots the magnetic field is zero inside the dot and constant outside. Such a device can be fabricated with present-day technology. We present detailed semiclassical studies of such magnetic anti-dot systems and provide a comparison with exact quantum calculations. In the semiclassical approach we apply the Berry-Tabor formula for the density of states and the Borh-Sommerfeld quantization rules. In both cases we found good agreement with the exact spectrum in the weak magnetic field limit. The energy spectrum for a given missing flux quantum is classified in six possible classes of orbits and summarized in a so-called phase diagram. We also investigate the current flow patterns of different quantum states and show the clear correspondence with classical trajectories.

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B. Kocsis, G. Palla, J. Cserti. 2004-07-09. Quantum and semiclassical study of magnetic anti-dots. https://doi.org/10.1103/physrevb.71.075331

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