Critical Conductance and Its Fluctuations at Integer Hall Plateau Transitions

摘要: Under periodic boundary condition in the transverse direction, we calculate averaged zero-temperature two-terminal conductance ($ $) and its statistical fluctuations $ for $n\le 4$) at critical point of integer quantum Hall plateau transitions. We find {\it universal} values =(0.58\pm0.03){e^2\over h}$, =({e^2\over h})^{2n}A_{2n}$, where $A_{2,4,6,8}=0.081\pm0.005$; $0.013\pm0.003$; $0.0026\pm0.005$; $(8\pm2)\times10^{-4}$ respectively. also determine leading finite size scaling corrections to these observables. Comparisons with experiments will be made.