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Simultaneous Excitation of Spins and Pseudospins in the Bilayer $ν=1$ Quantum Hall State

D. Terasawa·M. Morino·K. Nakada·S. Kozumi·A. Sawada·Z. F. Ezawa·N. Kumada·K. Muraki·Y. Hirayama·T. Saku
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Abstract

The tilting angular dependence of the energy gap was measured in the bilayer quantum Hall state at the Landau level filling $ν=1$ by changing the density imbalance between the two layers. The observed gap behavior shows a continuous transformation from the bilayer balanced density state to the monolayer state. Even a sample with 33 K tunneling gap shows the same activation energy anomaly reported by Murphy {\it et al.}. We discuss a possible relation between our experimental results and the quantum Hall ferromagnet of spins and pseudospins.

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D. Terasawa, M. Morino, K. Nakada, S. Kozumi, A. Sawada, Z. F. Ezawa, N. Kumada, K. Muraki, Y. Hirayama, T. Saku. 2004-03-19. Simultaneous Excitation of Spins and Pseudospins in the Bilayer $ν=1$ Quantum Hall State. https://doi.org/10.1016/j.physe.2003.11.214

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