Thermodynamic properties of frustrated arbitrary spin-S J1–J2 quantum Heisenberg antiferromagnet on the body-centered-cubic lattice in random phase approximation

Abstract

Abstract The thermodynamic properties of the frustrated arbitrary spin-S J1–J2 Heisenberg antiferromagnet on the body-centered-cubic lattice for Neel phase are systematically calculated by use of the double-time Green׳s function method within the random phase approximation (RPA). The role of spin quantum number and frustration strength on sublattice magnetization, Neel temperature, internal energy, and free energy are carefully analyzed. The curve of zero-temperature sublattice magnetization 〈 S z ( 0 ) 〉 / S versus frustration strength J2/J1 values are almost flat at the larger spin quantum number S=10. With the increase of normalized temperature T/TN, the larger the spin quantum number S, the faster the 〈 S z 〉 / S drops, and the smaller influence of J2/J1 on the 〈 S z 〉 / S versus T/TN curve. Under the RPA approach, the Neel temperature TN /Sp and the internal energy E/Sp at the Neel point are independent of spin quantum number S. The numerical results show that the internal energy E/Sp at the Neel point seems independent of the frustration strength J2/J1. This indicates that thermodynamic quantities have universal characteristics for large spin quantum number.