Two Dimensional Fermi Surfaces of CePtAs and CePtP Studied by the de Haas-van Alphen and Magnetoresistance Experiments

Abstract

We have found the cylindrical Fermi surfaces of CePtX (X=As, P) by the de Haas-van Alphen (dHvA) and magnetoresistance experiments. This is mainly due to the crystal structure, where the nearest neighbor distance between Pt and X atoms on the Pt-X plane is extremely short. The strong hybridization between the Pt 5 d ( x 2 - y 2 , x y ) and X p ( x , y ) states makes partially occupied anti-bonding bands, resulting in the cylindrical Fermi surfaces. The cyclotron effective mass is light, being in the range of 0.47 to 0.84 m 0 for CePtAs and 0.34 to 0.82 m 0 for CePtP. The present experimental results are well explained by the FLAPW band calculations.