Journal or Book Title
Physical Review Letters
The optical absorptivities of oriented single crystals of hcp Gd, Tb, Dy, Ho, Er, Tm, and Lu were measured at 4.2 K between 0.2 and 4.4 eV. Polarized radiation was used to reveal the optical anisotropy. Systematic movement of structures in the absorptivity and optical conductivity was observed as a result of trends within sp and d bands. Low-energy structures were related to effects of s−f exchange interaction, but were more complicated than previously thought.
The American Physical Society
Weaver, J. H. and Lynch, David W., "Anisotropic Optical Properties of Heavy-Rare-Earth Single Crystals" (1975). Physics and Astronomy Publications. 41.