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arXiv · 1301.7549

Matrix-Product Ansatz for Excited States of Fractional Quantum Hall Systems

Zheng-Yuan Wang·Masaaki Nakamura
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Abstract

Recently, it was discussed that the $\nu=1/3$ fractional quantum Hall state can be expressed by a one-dimensional lattice model with an exact matrix-prduct ground state, when toroidal boundary conditions are assumed for a narrow strip [Phys. Rev. Lett. {\bf 109} (2012) 016401]. In this article, we discuss how the excitation spectra of this system are calculated analytically based on the matrix-product formalism. We introduce variational wave functions for various momenta and optimize them. The obtained spectra of the charge neutral excitations show the magneto-roton behavior.

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Zheng-Yuan Wang, Masaaki Nakamura. 2013-01-31. Matrix-Product Ansatz for Excited States of Fractional Quantum Hall Systems. https://doi.org/10.7566/jpscp.4.013002

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