Motivated by the discovery of extremely low-energy collective modes in the fractional quantum Hall effect [Kang, Pinczuk et al., Phys. Rev. Lett. 84, 546 (2000)], with energies below the Zeeman energy, we study theoretically the spin-reversed excitations for fractional quantum Hall states at ν = 2/5 and 3/7 and find qualitatively different behavior than for ν = 2/5 We find that a low-energy, charge-neutral “spin roton,” associated with spin-reversed excitations that involve a change in the composite-fermion Landau level index, has energy in reasonable agreement with experiment.
|Original language||English (US)|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - May 7 2001|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics