Effects of Electron-Electron Interactions on the Integer Quantum Hall Transitions

We study the effects of the electron-electron interaction on the critical properties of the plateau transitions in the integer quantum Hall effect. We find the renormalization group dimension associated with short-range interactions to be -0.66±0.04. Thus the noninteracting fixed point (characterized z0ex0ex=0ex0ex2 and ν≈2.3) is stable. For the Coulomb interaction, we find the correlation effect is a marginal perturbation at a Hartree-Fock fixed point ( z0ex0ex=0ex0ex1, ν≈2.3) by dimension counting. Further calculations are needed to determine its stability upon loop corrections.