Competition between multi-channel Kondo effect and f delocalization in TmTe at high pressure

Jarrige, I.; Rueff, J.-P.*; Shieh, S.*; Taguchi, Munetaka*; Ishii, Hirofumi*; Cai, Y. Q.*

Identifying the mechanism of Kondo phenomena is arguably one of the most exciting and widely studied issues in condensed matter physics. Intermediate-valent Tm compounds stand out as potential candidates for multichannel Kondo (ncK) effect, since both integer valences Tm and Tm are magnetic. Using resonant inelastic X-ray scattering and the Anderson impurity model, we probed the Tm valence and 4f-5d hybridization in the high-pressure intermediate-valent TmTe compound. Our results reveal that the f delocalization is discontinuous, characterized by a previously unobserved plateau-like behavior over the 4.36.5 GPa range. This is at odds with the usual, continuous Kondo-like f delocalization, and is interpreted as an experimental observation of the effect of culminating ncK scattering of d electrons from local moments on the electronic structure.