Magnetic properties of the bond and crystal field dilution Blume-Emery-Griffiths model in the presence of magnetic field

摘要

The magnetic properties of the spin-1 bond and crystal field dilution Blume-Emery-Griffiths (BEG) model in the presence of magnetic field are investigated on a simple cubic lattice by using effective field theory (EFT). In the M-H plane, the common action of bond and crystal field dilution leads to the exhibition of an irregular initial magnetization curve and slows down the magnetization process. The peak of the susceptibility curve has an explicit decline and shows a distinct shift toward the direction of increase of magnetic field. On the other hand, in the M-T plane, the magnetization curves show a discontinuity and a vertical leap in the small range of magnetic field when the negative crystal field is larger and the ratio of biquadratic and exchange interaction is positive (alpha > 0). These results have not been revealed in previous works. (c) 2006 Elsevier Ltd. All rights reserved.