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The half-filled Landau level - composite fermions and dipoles

Felix von Oppen·Bertrand I. Halperin·Steven H. Simon·Ady Stern
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Abstract

The composite-fermion approach as formulated in the fermion Chern-Simons theory has been very successful in describing the physics of the lowest Landau level near Landau level filling factor 1/2. Recent work has emphasized the fact that the true quasiparticles at these filling factors are electrically neutral and carry an electric dipole moment. In a previous work, we discussed at length two formulations in terms of dipolar quasiparticles. Here we briefly review one approach - termed electron-centered quasiparticles - and show how it can be extended from 1/2 to nearby filling factors where the quasiparticles carry both an electric dipole moment and an overall charge.

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Felix von Oppen, Bertrand I. Halperin, Steven H. Simon, Ady Stern. 1999-04-28. The half-filled Landau level - composite fermions and dipoles. https://doi.org/10.1007/bfb0107478

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