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Magnetoresistance and conductivity exponents of quench-condensed ultra-thin films of Bi

K. Das Gupta·G. Sambandamurthy·V. H. S. Moorthy·N. Chandrasekhar
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Abstract

We have studied the magnetoresistance (MR) and evolution of conductivity with thickness of quench-condensed Bismuth films on substrates of various dielectric constants. Our results indicate a negative intial MR proportional to the square of the magnetic field. The conductance shows a power-law kind of dependence on thickness, with an exponent close to 1.33, characterisitic of a 2-D percolating system, only when the films are grown on a thin ($\sim 10${\rm Å} Germanium underlayer but not otherwise.

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K. Das Gupta, G. Sambandamurthy, V. H. S. Moorthy, N. Chandrasekhar. 1999-10-02. Magnetoresistance and conductivity exponents of quench-condensed ultra-thin films of Bi. https://arxiv.org/abs/cond-mat/9910018

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