Far-infrared optical properties of the pyrochlore spin ice compound Dy2Ti2O4
C.Z. Bi, J.Y. Ma, B.R. Zhao, Z. Tang, D. Yin, C.Z. Li, D.Z. Yao, J., Shi, and X.G. Qiu
TL;DR
This study investigates the far-infrared optical properties of Dy2Ti2O4, revealing phonon behavior, charge localization, and spin-phonon coupling effects in a spin ice compound through temperature-dependent reflectivity measurements.
Contribution
It provides detailed experimental analysis of phonon modes, charge dynamics, and spin-phonon interactions in Dy2Ti2O4 using far-infrared spectroscopy.
Findings
Identification of seven phonon modes below 1000 cm-1
Observation of phonon linewidth narrowing with decreasing temperature
Redshift of low-frequency modes indicating spin-phonon coupling
Abstract
Near normal incident far-infrared reflectivity spectra of [111] dysprosium titanate (Dy2Ti2O4) single crystal have been measured at different temperatures. Seven phonon modes (eight at low temperature) are identified at frequency below 1000 cm-1. Optical conductivity spectra are obtained by fitting all the reflectivity spectra with the factorized form of the dielectric function. Both the Born effective charges and the static optical primitivity are found to increase with decreasing temperature. Moreover, phonon linewidth narrowering and phonon modes shift with decreasing temperature are also observed, which may result from enhanced charge localization. The redshift of several low frequency modes is attributed to the spin-phonon coupling. All observed optical properties can be explained within the framework of nearest neighbor ferromagnetic(FM) spin ice model.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.