Multifractal properties of critical eigenstates in two-dimensional systems with symplectic symmetry

The multifractal properties of electronic eigenstates at the metal-insulator transition of a two-dimensional disordered tight-binding model with spin-orbit interaction are investigated numerically. The correlation dimensions of the spectral measure D̃2 and of the fractal eigenstate D2 are calculated and shown to be related by D2 = 2D̃2. The exponent η = 0.35 ± 0.05 describing the energy correlations of the critical eigenstates is found to satisfy the relation