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arXiv · 2410.00969

A Closed Band-Projected Density Algebra Must be Girvin-MacDonald-Platzman

Ziwei Wang·Steven H. Simon
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Abstract

The band-projected density operators in a Landau level obey the Girvin-MacDonald-Platzman (GMP) algebra, and a large amount of effort in the study of fractional Chern insulators has been directed towards approximating this algebra in a Chern band. In this paper, we prove that the GMP algebra, up to form factors, is the $\textit{only}$ closed algebra that projected density operators can satisfy in two and three dimensions, highlighting the central place it occupies in the study of Chern bands in general. A number of interesting corollaries follow.

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Ziwei Wang, Steven H. Simon. 2024-10-01. A Closed Band-Projected Density Algebra Must be Girvin-MacDonald-Platzman. https://arxiv.org/abs/2410.00969

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