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Doubly Enhanced Skyrmions in $ν=2$ Bilayer Quantum Hall States

N. Kumada·A. Sawada·Z. F. Ezawa·S. Nagahama·H. Azuhata·K. Muraki·T. Saku·Y. Hirayama
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Abstract

By tilting the samples in the magnetic field, we measured and compared the Skyrmion excitations in the bilayer quantum Hall (QH) state at the Landau-level filling factor $ν=2$ and in the monolayer QH state at $ν=1$. The observed number of flipped spins is $N_s=14$ in the bilayer system with a large tunneling gap, and $N_s=7$ in the bilayer system with a small tunneling gap, while it is $N_s=7$ in the monolayer system. The difference is interpreted due to the interlayer exchange interaction. Moreover, we have observed seemingly preferred numbers $N_s=14,7,1$ for the flipped spins by tilting bilayer samples.

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N. Kumada, A. Sawada, Z. F. Ezawa, S. Nagahama, H. Azuhata, K. Muraki, T. Saku, Y. Hirayama. 2000-04-16. Doubly Enhanced Skyrmions in $ν=2$ Bilayer Quantum Hall States. https://doi.org/10.1143/jpsj.69.3178

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