Lifting of multiphase degeneracy by quantum fluctuations
Abstract
We study the effect of quantum fluctuations on the multiphase point of the Heisenberg model with first and secondneighbor competing interactions and strong uniaxial spin anisotropy D. By studying the structure of perturbation theory we show that the multiphase degeneracy which exists for S=∞ (i.e., for the axial nextnearestneighbor Ising model) is lifted and that the effect of quantum fluctuations is to stabilize a sequence of phases of wavelength 4,6,8, . . . . This sequence is probably an infinite one. We also show that quantum fluctuations can mediate an infinite sequence of layering transitions through which an interface can unbind from a wall.
 Publication:

Physical Review B
 Pub Date:
 September 1995
 DOI:
 10.1103/PhysRevB.52.6684
 arXiv:
 arXiv:condmat/9505018
 Bibcode:
 1995PhRvB..52.6684H
 Keywords:

 75.30.Et;
 71.70.Ej;
 75.30.Gw;
 Exchange and superexchange interactions;
 Spinorbit coupling Zeeman and Stark splitting JahnTeller effect;
 Magnetic anisotropy;
 Condensed Matter
 EPrint:
 55 pages ReVTeX (encoded with uufiles) + 17 uuencoded figures