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arXiv · 2105.14101

Pressure-induced structural transitions triggering dimensional crossover in lithium purple bronze Li0.9M6O17

M. K. Tran·A. Akrap·J. Levallois·J. Teyssier·P. Schouwink·C. Besnard·P. Lerch·J. W. Allen·M. Greenblatt·D. van der Marel
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Abstract

At ambient pressure, lithium molybdenum purple bronze (Li0.9Mo6O17) is a quasi-one dimensional solid in which the anisotropic crystal structure and the linear dispersion of the underlying bands produced by electronic correlations possibly bring about a rare experimental realization of Tomomaga-Luttinger liquid physics. It is also the sole member of the broader purple molybdenum bronzes family where a Peierls instability has not been identified at low temperatures. The present study reports a pressure-induced series of phase transitions between 0 and 12 GPa. These transitions are strongly reflected in infrared spectroscopy, Raman spectroscopy, and x-ray diffraction. The most dramatic effect seen in optical conductivity is the metallization of the c-axis, concomitant to the decrease of conductivity along the b-axis. This indicates that high pressure drives the material away from its quasi-one dimensional behavior at ambient pressure. While the first pressure-induced structure of the series is resolved, the identification of the underlying mechanisms driving the dimensional change in the physics remains a challenge.

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M. K. Tran, A. Akrap, J. Levallois, J. Teyssier, P. Schouwink, C. Besnard, P. Lerch, J. W. Allen, M. Greenblatt, D. van der Marel. 2021-05-28. Pressure-induced structural transitions triggering dimensional crossover in lithium purple bronze Li0.9M6O17. https://doi.org/10.1103/physrevb.103.235124

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