Evolution of the Kondo lattice and non-Fermi liquid excitations in a heavy-fermion metal

• DOI: 10.1038/s41467-018-05801-5
• Publication Date: 2018-08-14T10:07:33Z
• Authors: S. Seiro; L. Jiao; S. Kirchner; S. Hartmann; S. Friedemann; C. Krellner; C. Geibel; Q. Si; F. Steglich; S. Wirth
• Keywords: Kondo insulator; Lattice (music); Strongly correlated material

Strong electron correlations can give rise to extraordinary properties of metals with renormalized Landau quasiparticles. Near a quantum critical point, these quasiparticles be destroyed and non-Fermi liquid behavior ensues. YbRh2Si2 is prototypical correlated metal exhibiting the formation quasiparticle Kondo lattice coherence, as well destruction at field-induced point. Here we show how, upon lowering temperature, coherence develops zero field finally gives way electronic excitations. By measuring single-particle excitations through scanning tunneling spectroscopy, find peak displays non-trivial temperature dependence strong increase around 3.3 K. At 0.3 K applied magnetic field, width this minimized in regime. Our results demonstrate that have sufficiently developed before criticality set in.