K. N. Boldyrev, E. V. Mostovschikova, A. N. Titov, V. Ya. Pokrovskii, I. G. Gorlova, “Infrared transmission spectra of TiS<nobr>$_3$</nobr>: fundamental absorption edge, phonons, and excitons”, Pis'ma v Zh. Èksper. Teoret. Fiz., 2024, Volume 120, Issue 8,Pages <nobr>590

This article is cited in 3 papers

OPTICS AND NUCLEAR PHYSICS

Infrared transmission spectra of TiS$_3$: fundamental absorption edge, phonons, and excitons

K. N. Boldyrev^a, E. V. Mostovschikova^b, A. N. Titov^b, V. Ya. Pokrovskii^c, I. G. Gorlova^c

^a Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow, 108840 Russia
^b Mikheev Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, Yekaterinburg, 620108 Russia
^c Kotel’nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, Moscow, 125009 Russia

Abstract: Transmission spectra of TiS$_3$ single crystal whiskers in the infrared and optical bands have been studied at various light polarizations in the temperature range from room to liquid helium. The absolute absorption coefficients have been determined. Previously unknown phonon modes have been observed in the far infrared region. The study of the temperature dependence of the band gap width ${{\mathcal{E}}_{{\text{g}}}}$ has shown that it increases by 50 meV under cooling from 300 to 5 K. The comparison of spectra measured at different polarization directions indicates that the optical gap is anisotropic. A 1.28-eV absorption peak has been detected below $\sim$ 150 K and has been attributed to the excitation of excitons.

Received: 02.06.2024
Revised: 09.09.2024
Accepted: 09.09.2024

DOI: 10.31857/S0370274X24100164