https://doi.org/10.1007/s100510170324
Charge excitations in heavy electron metals
1
Laboratorium für Festkörperphysik ETH-Zurich, 8093 Zurich, Switzerland
2
Institut für Festkörperphysik, Technical University Darmstadt, 64283 Darmstadt, Germany
3
Department of Physics and Astronomy, University of California at Los Angeles, Los Angeles CA 90095-1547,
USA
Corresponding author: a degiorgi@solid.phys.ethz.ch
Received:
28
August
2000
Revised:
31
October
2000
Published online: 15 January 2001
We show that the optical response of metals with strong electron-electron correlation consists of two excitations, a renormalized Drude response at zero energy and a mid-infrared peak occurring at frequencies around 2000 cm-1. The latter originates from a dynamical, correlation-induced gap, as evinced from a many body theoretical approach based on the periodic Anderson model. At very low temperatures, it can be viewed as optical gap between two renormalized quasi-particle bands. The gap size is proportional to the geometric mean of the characteristic lattice Kondo temperature of the material and its bandwidth.
PACS: 78.20.-e – Optical properties of bulk materials and thin films / 71.28.+d – Narrow-band systems; intermediate-valence solids
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001