Magnetic Properties of Rare-Earth Monopnictides in High Magnetic Fields

摘要: Since more than two decades, the physics of rare-earth compounds has been particular interest because variety their magnetic properties, classified as valence fluctuations and heavy fermions. In Ce compounds, changes between +3 (4f1) +2 (4f0) in some materials called fluctuation systems, although is normally supposed to be (4f1). The very small excitation energy for Yb leads an intermediate state by hybridization 4f states neigh-boring atoms, creates a resonance scattering band near Fermi level E F. width about Δ = πN F V 2, where amplitude N density (DOS) conduction Therefore, DOS at surface enhanced on order 1/Δ. Some show heavy-fermion behavior. A typical material CeAl3. As result F, effective mass hundred or thousand times larger that normal metals. At low temperatures, mixing orbital itinerant bands results excessively narrow quasi-particle level. Sommerfeld coefficient g proportional γ 1.6 JK−2 mol−1 CeAl3 [11]. While metal, copper, 0.7 mJK−2 mol−1. strong enhancement occurs We can know only total interactions electrons from specific heat measurements.