Kondo insulator to antiferromagnet transition in heavy-fermion compounds

We study the symmetric Kondo lattice model by a variational Monte-Carlo approach in one and two dimensions. While in one dimension a Kondo insulator is always stable, by tuning the Kondo coupling we find a continuous phase transition between a Kondo insulator and an antiferromagnetic state in two dimensions. We compare this result with the recent experimental observations of the Kondo insulator and antiferromagnetic phases in ternary compounds CeNi1-x(Pd,Pt)xSn. © 1994.