FINITE-SIZE-SCALING OF MULTIFRACTAL WAVE-FUNCTIONS - THE METAL-INSULATOR-TRANSITION IN 2-DIMENSIONAL SYMPLECTIC SYSTEMS

A finite-size scaling analysis of wave functions near the metal-insula tor transition (MIT) point has been developed, and applied to the MIT in a two-dimensional disordered electron system in the presence of spi norbit interaction. The present method has the following advantages: ( i) Quantities characterizing the critical behavior, such as the critic al disorder W-c or the localization exponent nu, are multiply calculat ed from independent scaling analyses of spatial parts with different i ntensities in wave functions. (ii) These quantities and the multifract ality of the critical wave function are determined simultaneously. (ii i)It is not necessary to treat many samples with different sizes. (iv) Much computing time is saved, and the scaling analysis can be done up to very large sizes. Using this method, we obtained W-c=5.86+/-0.04 a nd nu= 2.41+/-0.24 for a model of a two-dimensional symplectic system. [S0163-1829(98)08039-4].