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arXiv · 2111.10593

Multiple Magnetorotons and Spectral Sum Rules in Fractional Quantum Hall Systems

Dung Xuan Nguyen·F. D. M. Haldane·E. H. Rezayi·Dam Thanh Son·Kun Yang
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Abstract

We study numerically the the charge neutral excitations (magnetorotons) in fractional quantum Hall systems, concentrating on the two Jain states near quarter filling, $\nu=2/7$ and $\nu=2/9$, and the $\nu=1/4$ Fermi-liquid state itself. In contrast to the $\nu=1/3$ states and the Jain states near half filling, on each of the two Jain states $\nu=2/7$ and $\nu=2/9$ the graviton spectral densities show two, instead of one, magnetoroton peaks. The magnetorotons have spin 2 and have opposite chiralities in the $\nu=2/7$ state and the same chirality in the $\nu=2/9$ state. We also provide a numerical verification of a sum rule relating the guiding center spin $\bar s$ with the spectral densities of the stress tensor

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Dung Xuan Nguyen, F. D. M. Haldane, E. H. Rezayi, Dam Thanh Son, Kun Yang. 2021-11-20. Multiple Magnetorotons and Spectral Sum Rules in Fractional Quantum Hall Systems. https://doi.org/10.1103/physrevlett.128.246402

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