Journal of the Physical Society of Japan
Tricritical Behavior of an Ising Antiferromagnet with Next-Nearest Neighbor Ferromagnetic Interaction
Chikao Kawabata, Jos Rogiers, G. F. Tuthill, Eugene Stanley
Abstract
Using high temperature series expansions, we have studied an Ising model with nearest-neighbor antiferromagnetic interaction ( J 1 <0) and next nearest neighbor ferromagnetic interaction ( J 2 >0), which is thought to exhibit a tricritical point (TCP). Assuming that tricritical exponents are mean-field like, we locate TCPs for several values of the exchange coupling parameter J 2 / J 1 by the method of log-Padé analysis.