We present an application of high-order series expansion in the coupling constants for the ground-state properties of correlated lattice fermion systems. Expansions have been generated up to order (t/J${)}^{14}$ for d=1 and (t/J${)}^8$ for d=2,3 for certain properties of the symmetric Kondo-lattice model. Analyzing the susceptibility series, we find evidence for a continuous phase transition from the spin-liquid phase characteristic of a Kondo insulator to an antiferromagnetically ordered phase in dimensions d≥2 as the antiferromagnetic Kondo coupling is decreased. The critical point is estimated to be at (t/J${)}_{\mathit{c}}$≊0.7 for a square lattice and (t/J${)}_{\mathit{c}}$≊0.5 for a simple-cubic lattice.

• Received 23 March 1995

DOI:https://doi.org/10.1103/PhysRevB.51.15630