Critical regime of two dimensional Ando model: relation between critical conductance and fractal dimension of electronic eigenstates
نویسندگان
چکیده
The critical two-terminal conductance gc and the spatial fluctuations of critical eigenstates are investigated for a disordered two dimensional model of non-interacting electrons subject to spin-orbit scattering (Ando model). For square samples, we verify numerically the relation σc = 1/[2π(2−D(1))] e /h between critical conductivity σc = gc = (1.42 ± 0.005) e /h and the fractal information dimension of the electron wave function, D(1) = 1.889 ± 0.001. Through a detailed numerical scaling analysis of the two-terminal conductance we also estimate the critical exponent ν = 2.80± 0.04 that governs the quantum phase transition. Critical conductance and wavefunction of two dimensional Ando model 2
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