First principles calculation and experimental investigation of lattice dynamics in the rare earth pyrochlores R2Ti2O7 (R=Tb, Dy, Ho)

Abstract

We present a model of the lattice dynamics of the rare earth titanate pyrochlores R2Ti2O7 (R=Tb, Dy, Ho), which are important materials in the study of frustrated magnetism. The phonon modes are obtained by density functional calculations, and these predictions are verified by comparison with scattering experiments. Single crystal inelastic neutron scattering is used to measure acoustic phonons along high symmetry directions for R=Tb, Ho; single crystal inelastic x-ray scattering is used to measure numerous optical modes throughout the Brillouin zone for R=Ho; and powder inelastic neutron scattering is used to estimate the phonon density of states for R=Tb, Dy, Ho. Good agreement between the calculations and all measurements is obtained, allowing confident assignment of the energies and symmetries of the phonons in these materials under ambient conditions. The knowledge of the phonon spectrum is important for understanding spin-lattice interactions, and can be expected to be transferred readily to other members of the series to guide the search for unconventional magnetic excitations.

arXiv comment15 pages, 11 figures

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Cited by in corpus (23)

• Crystal field parameters of the rare earth pyrochlores $R_2$Ti${}_2$O${}_7$ ($R$ = Tb, Dy, Ho)
• Role of defects in determining the magnetic ground state of ytterbium titanate
• Emergent Electrochemistry in Spin Ice: Debye-Hückel Theory and Beyond
• Magneto-elastic induced vibronic bound state in the spin ice pyrochlore Ho${}_2$Ti${}_2$O${}_7$
• Dipolar-Octupolar Ising Antiferromagnetism in Sm${}_2$Ti${}_2$O${}_7$: A Moment Fragmentation Candidate
• Half moons are pinch points with dispersion
• Double Vibronic process in the quantum spin ice candidate Tb${}_2$Ti${}_2$O${}_7$ revealed by terahertz spectroscopy
• Phonon-mediated spin-flipping mechanism in the spin ices Dy${}_2$Ti${}_2$O${}_7$ and Ho${}_2$Ti${}_2$O${}_7$
• Introduction to High-Resolution Inelastic X-Ray Scattering
• Neutron Larmor diffraction investigation of the rare earth pyrochlores $R_2$Ti${}_2$O${}_7$ ($R$ = Tb, Dy, Ho)
• Intermultiplet transitions and magnetic long-range order in Sm-based pyrochlores
• Infrared phonons as a probe of a spin-liquid states in herbertsmithite ZnCu3(OH)6Cl2
• Continuum excitation and pseudospin wave in quantum spin-liquid and quadrupole ordered states of Tb${}_{2+x}$Ti${}_{2-x}$O${}_{7+y}$
• Crystal field excitations from $\mathrm{Y}{\mathrm{b}}^{3+}$ ions at defective sites in highly stuffed $\mathrm{Y}{\mathrm{b}}_2\mathrm{T}{\mathrm{i}}_2{\mathrm{O}}_7$
• Giant Grüneisen parameter in a strain-tuned superconducting quantum paraelectric: A consequence of the vanishing ferroelectric phonon energy
• Phonon thermal Hall effect in non-magnetic Y${}_2$Ti${}_2$O${}_7$
• Synthesis of epitaxial magnetic pyrochlore heterojunctions
• Thermodynamic properties of quadrupolar states in the frustrated pyrochlore magnet Tb${}_2$Ti${}_2$O${}_7$
• Probing emergent QED in quantum spin ice via Raman scattering of phonons: shallow inelastic scattering and pair production
• Crystal-field magnetostriction of the spin ice under ultrahigh magnetic fields
• Anomalous out-of-equilibrium dynamics in the spin-ice material Dy${}_2$Ti${}_2$O${}_7$ under moderate magnetic fields
• Low-temperature specific heat and heat transport of Tb${}_2$Ti${}_{2-x}$Zr${}_x$O${}_7$ single crystals
• Kagome modes, a new route to ultralow thermal conductivity?