Far-infrared optical properties of the pyrochlore spin ice compound Dy2Ti2O4

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.

References in corpus (8)

• Dipolar Interactions and Origin of Spin Ice in Ising Pyrochlore Magnets
• Long Range Order at Low Temperature in Dipolar Spin Ice
• Low Temperature Spin Freezing in Dy2Ti2O7 Spin Ice
• Magnetic anisotropy of the spin ice compound Dy2Ti2O7
• Charge transfer in the high dielectric constant materials CaCu3Ti4O12 and CdCu3Ti4O12
• Anisotropic Release of the Residual Zero-point Entropy in the Spin Ice Compound Dy2Ti2O7: Kagome-ice Behavior
• Field Induced Partial Order in the Spin-Ice Dysprosium Titanate
• Ordered Phase of the Dipolar Spin Ice under [110]-Magnetic Fields

Cited by in corpus (4)

• Temperature dependent Raman and x-ray studies of spin-ice pyrochlore $D{y}_{2}T{i}_2{O}_7$ and non-magnetic pyrochlore $L{u}_{2}T{i}_2{O}_7$
• Low temperature and high pressure Raman and x-ray studies of pyrochlore Tb${}_2$Ti${}_2$O${}_7$ : phonon anomalies and possible phase transition
• Possible Quantum Diffusion of Polaronic Muons in Dy${}_2$Ti${}_2$O${}_7$ Spin Ice
• Magnetic field tuning of crystal field levels and vibronic states in Spin-ice Ho${}_2$Ti${}_2$O${}_7$ observed in far-infrared reflectometry