Phonon and crystal field excitations in geometrically frustrated rare earth titanates

  title={Phonon and crystal field excitations in geometrically frustrated rare earth titanates},
  author={T T A Lummen and I P Handayani and Michiel C. Donker and Daniele Fausti and Guy Dhalenne and Patrick Berthet and Alexandre Revcolevschi and Paul H.M. van Loosdrecht},
  journal={Physical Review B},
The phonon and crystal field excitations in several rare earth titanate pyrochlores are investigated. Magnetic measurements on single crystals of Gd(2)Ti(2)O(7), Tb(2)Ti(2)O(7), Dy(2)Ti(2)O(7), and Ho(2)Ti(2)O(7) are used for characterization, while Raman spectroscopy and terahertz time domain spectroscopy are employed to probe the excitations in the materials. The lattice excitations are found to be analogous across the compounds over the whole temperature range investigated (295-4 K). The… 

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