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Quantum Hall Solitons with Intertwined Spin and Pseudospin at $ν= \ 1$

Sankalpa Ghosh·R. Rajaraman
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Abstract

In this paper we study in detail different types of topological solitons which are possible in bilayer quantum Hall systems at filling fraction $ν=1$ when spin degrees of freedom are included. Starting from a microscopic Hamiltonian we derive an effective energy functional for studying such excitations. The gauge invariance and $CP^{3}$ character of this energy fuctional and their consequences are examined. Then we identify permissible classes of finite energy solutions which are topologically non-trivial. We also numerically evaulate a representative solution in which a pseudospin (layer degrees of freedom) bimeron in a given spin component is intertwined with spin-skyrmions in each layer, and and discuss whether it is energetically favoured as the lowest lying excitation in such system with some numerical results.

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Sankalpa Ghosh, R. Rajaraman. 2000-07-31. Quantum Hall Solitons with Intertwined Spin and Pseudospin at $ν= \ 1$. https://doi.org/10.1103/physrevb.63.035304

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