Asymptotic behaviour in the spin excitation gap of the disordered Ce3Bi4Pt3

Abstract

The Kondo Lattice Model (KLM) is one of the most important models for studying heavy fermion (HF) systems. It has been extensively used to study Cerium based alloys like Ce₃Bi₄Pt₃ which is a Kondo Model Valence system. The Pb-doping of Ce₃(Bi_1-xPb_x)₄Pt₃ will produce similar results just like other kondo systems such as CeNi_xCu_1-x, Ce₂Au_1-xCo_xSi₃ and UCu_5-xPd_x etc. The role of the concentration, x, experimentally is analogous to the role of the spin gap, ∆s theoretically. The reduction in the electron density of the conduction electrons by a Pb-doping of Ce₃(Bi_1-xPb_x)₄Pt₃ enhances a magnetic ground state. This is analogous to the gradual reduction of the ∆s. It was observed that the ferromagnetic increase of the kondo interaction coupling, J, reduces the spin gap of the system.