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

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New low-lying excitations are observed by inelastic light scattering at filling factors ν=p/(ϕp ± 1) of the fractional quantum Hall regime with ϕ=4. Coexisting with these modes throughout the range ν≤ 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 1/3 suggests a marked change in the quantum ground state on crossing the ϕ=2 → ϕ=4 boundary at ν= 1/3.