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arXiv · 1109.1980

Absence of anomalous negative lattice-expansion for polycrystalline sample of Tb2Ti2O7

Kazuki Goto·Hiroshi Takatsu·Tomohiro Taniguchi·Hiroaki Kadowaki
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Abstract

High resolution X-ray powder-diffraction experiments on a well-characterized polycrystalline sample of the spin liquid Tb2Ti2O7 reveal that it shows normal positive thermal-expansion above 4 K, which does not agree with the intriguing anomalous negative thermal-expansion due to a magneto-elastic coupling reported for a single crystal sample below 20 K. We also performed a Rietveld profile refinement of a powder-diffraction pattern taken at a room temperature, and confirmed that it is consistent with the fully ordered cubic pyrochlore structure.

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Kazuki Goto, Hiroshi Takatsu, Tomohiro Taniguchi, Hiroaki Kadowaki. 2011-11-07. Absence of anomalous negative lattice-expansion for polycrystalline sample of Tb2Ti2O7. https://doi.org/10.1143/jpsj.81.015001

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