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

Mie 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 5d(x(2) - y(2), xy) 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 mo for CePtAs and 0.34 to 0.82 m(0) for CePtP. The present experimental results are well explained by the FLAPW band calculations.