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Critical Behavior of the Conductivity of Si:P at the Metal-Insulator Transition under Uniaxial Stress

S. Waffenschmidt·C. Pfleiderer·H. v. Loehneysen
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Abstract

We report new measurements of the electrical conductivity sigma of the canonical three-dimensional metal-insulator system Si:P under uniaxial stress S. The zero-temperature extrapolation of sigma(S,T -> 0) ~§- S_cmu shows an unprecidentedly sharp onset of finite conductivity at S_c with an exponent mu = 1. The value of mu differs significantly from that of earlier stress-tuning results. Our data show dynamical sigma(S,T) scaling on both metallic and insulating sides, viz. sigma(S,T) = sigma_c(T) F(§- S_cT^y) where sigma_c(T) is the conductivity at the critical stress S_c. We find y = 1/znu = 0.34 where nu is the correlation-length exponent and z the dynamic critical exponent.

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S. Waffenschmidt, C. Pfleiderer, H. v. Loehneysen. 1999-05-20. Critical Behavior of the Conductivity of Si:P at the Metal-Insulator Transition under Uniaxial Stress. https://doi.org/10.1103/physrevlett.83.3005

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