Issue
EPL
Volume 84, Number 6, December 2008
Article Number 67006
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
DOI http://dx.doi.org/10.1209/0295-5075/84/67006
Published online 07 January 2009
EPL, 84 (2008) 67006
DOI: 10.1209/0295-5075/84/67006

Matrix product representations for spin-(1/2) and spin-(3/2) spontaneous quantum ferrimagnets

S. Alipour1, S. Baghbanzadeh2 and V. Karimipour1

1   Department of Physics, Sharif University of Technology - P.O. Box 11155-9161, Tehran, Iran
2   Department of Physics, Iran University of Science and Technology - P.O. Box 16765-163, Tehran, Iran

salipour@physics.sharif.edu
sbaghbanzadeh@physics.iust.ac.ir
vahid@sharif.edu

received 16 June 2008; accepted in final form 5 November 2008; published December 2008
published online 7 January 2009

Abstract
Using the matrix product formalism, we find exact ground states for two new spin-() and spin-() quantum chains. On a lattice of sites, these ground states have a total spin of , and hence have ferrimagnetic character. The novel point of this construction is that we construct a matrix product representation, not for a state which is invariant under rotation as has been hitherto considered, but for a state which transforms to other states under this symmetry operation. The method can be directly generalized to other symmetry groups.

PACS
75.10.Jm - Quantized spin models.
03.67.-a - Quantum information.

© EPLA 2008