Infrared phonon spectra of quasi-one-dimensional Ta${}_2$NiSe${}_5$ and Ta${}_2$NiS${}_5$

T. I. Larkin, R. D. Dawson, M. Höppner +6

Using a combination of infrared ellipsometry, time-domain terahertz spectroscopy, and far-infrared reflectometry we have obtained the $ac$-plane complex dielectric function of mono…