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Crossover and Coexistence of Quasiparticle Excitations in the Fractional Quantum Hall Regime at $ν\leq 1/3$

C. F. Hirjibehedin·A. Pinczuk·B. S. Dennis·L. N. Pfeiffer·K. W. West
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Abstract

New low-lying excitations are observed by inelastic light scattering at filling factors $ν=p/(ϕp \pm 1)$ of the fractional quantum Hall regime with $ϕ=4$. Coexisting with these modes throughout the range $ν\leq 1/3$ are $ϕ=2$ excitations seen at 1/3. Both $ϕ=2$ and $ϕ=4$ excitations have distinct behaviors with temperature and filling factor. The abrupt first appearance of the new modes in the low energy excitation spectrum at $ν\lesssim 1/3$ suggests a marked change in the quantum ground state on crossing the $ϕ=2 \to ϕ=4$ boundary at $ν= 1/3$.

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C. F. Hirjibehedin, A. Pinczuk, B. S. Dennis, L. N. Pfeiffer, K. W. West. 2003-06-05. Crossover and Coexistence of Quasiparticle Excitations in the Fractional Quantum Hall Regime at $ν\leq 1/3$. https://doi.org/10.1103/physrevlett.91.186802

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