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arXiv · 2503.06914

Spin of fractional quantum Hall neutral modes and "missing states" on a sphere

Dung Xuan Nguyen·Dam Thanh Son
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Abstract

A low-energy neutral quasiparticle in a fractional quantum Hall system appears in the latter's energy spectrum on a sphere as a series of many-body excited states labeled by the angular momentum $L$ and whose energy is a smooth function of $L$ in the limit of large sphere radius. We argue that the signature of a nonvanishing spin (intrinsic angular momentum) $s$ of the quasiparticle is the absence, in this series, of states with total angular momentum less than $s$.We reinterpret the missing of certain states, observed in an exact-diagonalization calculation of the spectrum of the $\nu=7/3$ FQH state in a wide quantum well as well as in many proposed wave functions for the excited states as a consequence of the spin-2 nature of the zero-momentum magnetoroton.

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Dung Xuan Nguyen, Dam Thanh Son. 2025-03-10. Spin of fractional quantum Hall neutral modes and "missing states" on a sphere. https://doi.org/10.21468/scipostphys.19.5.131

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