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Surface critical behavior of random systems at the special transition

Z. Usatenko·Chin-Kun Hu
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Abstract

We study the surface critical behavior of semi-infinite quenched random Ising-like systems at the special transition using three dimensional massive field theory up to the two-loop approximation. Besides, we extend up to the next-to leading order, the previous first-order results of the $\sqrtε$ expansion obtained by Ohno and Okabe [Phys. Rev. B 46, 5917 (1992)]. The numerical estimates for surface critical exponents in both cases are computed by means of the Pade analysis. Moreover, in the case of the massive field theory we perform Pade-Borel resummation of the resulting two-loop series expansions for surface critical exponents. The obtained results confirm that in a system with quenched bulk randomness the plane boundary is characterized by a new set of surface critical exponents.

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Z. Usatenko, Chin-Kun Hu. 2001-05-09. Surface critical behavior of random systems at the special transition. https://doi.org/10.1103/physreve.65.066103

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