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.
@article{arxiv.2105.14101,
title = {Pressure-induced structural transitions triggering dimensional crossover in lithium purple bronze Li0.9M6O17},
author = {M. K. Tran and A. Akrap and J. Levallois and J. Teyssier and P. Schouwink and C. Besnard and P. Lerch and J. W. Allen and M. Greenblatt and D. van der Marel},
journal= {arXiv preprint arXiv:2105.14101},
year = {2021}
}