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Inelastic Light Scattering by Gap Excitations of Fractional Quantum Hall States at 1/3 <= ν<= 2/3

Moonsoo Kang·A. Pinczuk·B. S. Dennis·M. A. Eriksson·L. N. Pfeiffer·K. W. West
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Abstract

We report observations of collective gap excitations of the fractional quantum Hall (FQH) states at filling factors ν=p/(2p+1) (p=integer), for 1/3 <= ν<= 2/3, by inelastic light scattering. The collective gap energies at ν= 1/3, 2/5 and 3/7 show a drastic decrease as the value ν=1/2 is approached. These energies and the one at ν=3/5 display the linear scaling with (e^2/εl_o)/|2p+1| that is characteristic of composite fermions in Chern-Simons gauge fields. In a narrow range of νcentered at 1/2, where the FQH gaps collapse, we observe a new excitation mode which exists only at temperatures below 150 mK.

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Moonsoo Kang, A. Pinczuk, B. S. Dennis, M. A. Eriksson, L. N. Pfeiffer, K. W. West. 1999-11-22. Inelastic Light Scattering by Gap Excitations of Fractional Quantum Hall States at 1/3 <= ν<= 2/3. https://doi.org/10.1103/physrevlett.84.546

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