arXiv subjects

Lev Mikheev

Publications and source records attributed to Lev Mikheev.

2 recordsLinked to original sources

arXiv1995

Critical phenomena in superlattices: Reentrant dimensional crossover and anomalous critical amplitudes

A crossover from $d$ to $d-1$, and then back to $d$-dimensional critical behavior is argued to be a generic feature characterizing ordering in a $d$-dimensional superlattice composed of atomically {\em thick} films of two ferromagnets. The crossover leads to anomalous changes in the amplitudes of critical singularities. In $d=3$ Heisenberg and $XY$ superlattices large scale critical fluctuations persist over a wide temperature range.

cond-mat↗

arXiv1995

From surface to random criticality in layered planar Ising models

A general case of a spatially nonuniform planar layered Ising model, or an equivalent quantum Ising chain, is analysed with an exact functional real space renormalization group. Various surface, finite size, quasiperiodic and random layer (McCoy-Wu) universality classes are obtained and discussed within a single theoretical framework leading to new insights into the nature of random criticality.

cond-mat↗