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Skyrmions in the Moore-Read state at nu=5/2
Arkadiusz Wójs1, Gunnar Möller, Steven H Simon
1TCM Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom.
Physical Review Letters
|April 7, 2010
Summary
Charged excitations in the non-Abelian Moore-Read liquid can form Skyrmions at low Zeeman energy. Disorder promotes Skyrmion formation, potentially leading to a depolarized ground state at nu=5/2.
Area of Science:
- Condensed Matter Physics
- Quantum Hall Effect
Background:
- The non-Abelian Moore-Read liquid at filling factor nu=5/2 exhibits complex charged excitations.
- Understanding these excitations is crucial for characterizing the quantum Hall state.
Purpose of the Study:
- Investigate the behavior of charged excitations in the non-Abelian Moore-Read liquid.
- Determine conditions favoring the formation of Skyrmions from quasiholes.
- Assess the impact of disorder and Zeeman energy on the ground state.
Main Methods:
- Numerical studies of charged excitations.
- Consideration of non-zero well widths and Zeeman energy.
- Analysis of Skyrmion formation and its dependence on disorder.
Main Results:
- Charge e/4 quasiholes energetically favor binding into charge e/2 Skyrmions at low Zeeman energy.
- Disorder significantly promotes Skyrmion formation.
- Skyrmion formation can lead to a depolarized nu=5/2 ground state.
Conclusions:
- Skyrmion formation is a key mechanism in the non-Abelian Moore-Read liquid.
- Disorder plays a critical role in achieving a depolarized ground state.
- These findings have implications for understanding activated transport in realistic systems.
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