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arXiv · 0709.4306

Modulation of bilayer quantum Hall states by tilted-field-induced subband-Landau-level coupling

N. Kumada·K. Iwata·K. Tagashira·Y. Shimoda·K. Muraki·Y. Hirayama·A. Sawada
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Abstract

We study effects of tilted magnetic fields on energy levels in a double-quantum-well (DQW) system, focusing on the coupling of subbands and Landau levels (LLs). The subband-LL coupling induces anticrossings between LLs, manifested directly in the magnetoresistance. The anticrossing gap becomes larger than the spin splitting at the tilting angle $θ\sim 20^\circ $ and larger than the cyclotron energy at $θ\sim 50^\circ $, demonstrating that the subband-LL coupling exerts a strong influence on quantum Hall states even in at a relatively small $θ$ and plays a dominant role for larger $θ$. We also find that when the DQW potential is asymmetric, LL coupling occurs even within a subband. Calculations including higher-order coupling reproduce the experimental results quantitatively well.

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N. Kumada, K. Iwata, K. Tagashira, Y. Shimoda, K. Muraki, Y. Hirayama, A. Sawada. 2007-09-27. Modulation of bilayer quantum Hall states by tilted-field-induced subband-Landau-level coupling. https://doi.org/10.1103/physrevb.77.155324

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