Short-range interactions and scaling near integer quantum Hall transitions
- Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States)
- Institute for Theoretical Physics, University of California, Santa Barbara, California 93106-4030 (United States)
- Department of Physics, Indiana University, Bloomington, Indiana 47405 (United States)
- Theoretical Physics, Oxford University, Oxford OX1 3NP, (United Kingdom)
We study the influence of short-range electron-electron interactions on scaling behavior near the integer quantum Hall plateau transitions. Short-range interactions are known to be irrelevant at the renormalization group fixed point which represents the transition in the noninteracting system. We find, nevertheless, that transport properties change discontinuously when interactions are introduced. Most importantly, in the thermodynamic limit the conductivity at finite temperature is zero without interactions, but nonzero in the presence of arbitrarily weak interactions. In addition, scaling as a function of frequency {omega} and temperature T is determined by the scaling variable {omega}/T{sup p} (where p is the exponent for the temperature dependence of the inelastic scattering rate) and not by {omega}/T, as it would be at a conventional quantum phase transition described by an interacting fixed point. We express the inelastic exponent p and the thermal exponent z{sub T} in terms of the scaling dimension -{alpha}<0 of the interaction strength and the dynamical exponent z (which has the value z=2), obtaining p=1+2{alpha}/z and z{sub T}=2/p. (c) 2000 The American Physical Society.
- OSTI ID:
- 20215763
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Vol. 61, Issue 12; Other Information: PBD: 15 Mar 2000; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
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