Abstract
Gehring et al. argue that a splitting observed by us in the transverse acoustic (TA) phonon in the relaxor fer-roelectric Pb[(Mg 1/3 Nb 2/3 ) 1 − x Ti x ]O 3 with x = 0.30 (PMN-30PT) is caused by a combination of inelastic-elastic multiple scattering processes called ghostons. Their argument is motivated by differences observed between their measurements made on a triple-axis spectrometer and our measurements on a time-of-flight spectrometer. We show that the differences can be explained by differences in the instrument resolution functions. We demonstrate that the multiple scattering conditions proposed by Gehring et al. do not work for our scattering geometry. We also show that, when a ghoston is present, it is too weak to detect and therefore cannot explain the splitting. Last, this phonon splitting is just one part of the argument, and the overall conclusion of the original paper is supported by other results.
Original language | English |
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Article number | eaaw4367 |
Journal | Science Advances |
Volume | 5 |
Issue number | 3 |
DOIs | |
State | Published - 2019 |
Funding
This work was sponsored by the Office of Basic Energy Sciences, Materials Sciences and Engineering Division, U.S. Department of Energy. The portion of this research performed at the Oak Ridge National Laboratory’s Spallation Neutron Source was sponsored by the U.S. Department of Energy, Office of Basic Energy Sciences.