https://doi.org/10.1140/epjb/e2002-00390-7
Low temperature properties of the random field Potts chain
1
Theoretische Physik, Universität des Saarlandes,
66041 Saarbrücken, Germany
2
Helsinki University of Techn., Laboratory of Physics,
PO Box 1100, 02015 HUT, Finland
Corresponding author: a rieger@lusi-sb.de
Received:
27
August
2002
Published online:
19
December
2002
The random field q-states Potts model is investigated using
exact groundstates and finite-temperature transfer matrix
calculations. It is found that the domain structure and
the Zeeman energy of the domains resembles for general
q the random field Ising case (q=2). This is also
the expected outcome based on a random-walk picture of the
groundstate. The domain size distribution is
exponential, and the scaling of the average
domain size with the disorder strength is similar for
q arbitrary. The zero-temperature properties are
compared to the equilibrium spin states at small
temperatures, to investigate the effect of local random
field fluctuations that imply locally degenerate regions.
The response to field perturbations (`chaos')
and the susceptibility are investigated. In particular
for the chaos exponent it is found to be 1
for 
. Finally for q=2 (Ising case) the
domain length distribution is studied for correlated random fields.
PACS: 05.40.-a – Fluctuation phenomena, random processes, noise, and Brownian motion / 05.50.+q – Lattice theory and statistics (Ising, Potts, etc.) / 75.50.Lk – Spin glasses and other random magnets
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002
