Numéro
J. Phys. IV France
Volume 12, Numéro 9, November 2002
Page(s) 259 - 260
DOI http://dx.doi.org/10.1051/jp4:20020409


J. Phys. IV France
12 (2002) Pr9-259
DOI: 10.1051/jp4:20020409

Spin and charge ordering transitions in stripes

F. Kruger and S. Scheidl

Institut für Theoretische Physik, Universität zu Köln, Zulpicher Str. 77, 50937 Köln, Germany


Abstract
We study the interplay of topological excitations in stripe phases: charge dislocations, charge loops, and spin vortices. In two dimensions these defects interact logarithmically on large distances. Using a renormalization-group analysis in the Coulomb gas representation of these defects, we calculate the phase diagram and the critical properties of the transitions. Depending on the interaction parameters, spin and charge order can disappear at a single transition or in a sequence of two transitions (spin-charge separation). These transitions are non-universal with continuously varying critical exponents. We also determine the nature of the points where three phases coexist.



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