Abstract
The fractional quantum Hall state is a quintessential system for the study of collective quantum behaviour. In such a system, the collective behaviour results in the creation of so-called composite fermions, quasi-particles formed by electrons attached to magnetic flux quanta. Recently, a new collective mode was unexpectedly observed in Raman scattering experiments on such a system as it was found to split off from the familiar fundamental long-wavelength mode on increase of the wave vector. Here, we present results from extensive theoretical calculations that make a compelling case that this mode corresponds to an excitation of a composite fermion across two levelseffective kinetic energy levels resembling Landau levels for such particles. In addition to explaining why this excitation merges with the fundamental mode in the long-wavelength limit, our theory also provides a good quantitative account of the amount of splitting, and makes several experimentally verifiable predictions.
Original language | English (US) |
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Pages (from-to) | 403-406 |
Number of pages | 4 |
Journal | Nature Physics |
Volume | 5 |
Issue number | 6 |
DOIs | |
State | Published - Jun 2009 |
All Science Journal Classification (ASJC) codes
- General Physics and Astronomy