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Emergence of a real-space symmetry axis in the magnetoresistance of the one-dimensional conductor Li_0.9Mo₆O₁₇.

ABSTRACT: We report on an emerging symmetry axis in the magnetoresistance of bulk single crystals of quasi-one-dimensional Li_0.9Mo₆O₁₇ below T _min = 25 K, the temperature at which the electrical resistivity experiences a minimum. Detailed angle-dependent magnetoresistance sweeps reveal that this symmetry axis is induced by the development of a negative magnetoresistance, which is suppressed only for magnetic fields oriented along the poles of the MoO₆ octahedra that form the conducting chains. We show that this unusual negative magnetoresistance is consistent with the melting of dark excitons, composed of previously omitted orbitals within the t _2g manifold that order below T _min. The unveiled symmetry axis in directional magnetic fields not only provides evidence for the crystallization of these dark excitons but also sheds new light on the long-standing mystery of the metal-insulator transition in Li_0.9Mo₆O₁₇.

SUBMITTER: Lu J

PROVIDER: S-EPMC6611691 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Emergence of a real-space symmetry axis in the magnetoresistance of the one-dimensional conductor Li0.9Mo6O17.

Lu Jianming J Xu Xiaofeng X Greenblatt M M Jin R R Tinnemans P P Licciardello S S van Delft M R MR Buhot J J Chudzinski P P Hussey N E NE

Science advances 20190705 7

We report on an emerging symmetry axis in the magnetoresistance of bulk single crystals of quasi-one-dimensional Li0.9Mo6O17 below T min = 25 K, the temperature at which the electrical resistivity experiences a minimum. Detailed angle-dependent magnetoresistance sweeps reveal that this symmetry axis is induced by the development of a negative magnetoresistance, which is suppressed only for magnetic fields oriented along the poles of the MoO ...[more]

PMID: 31281877

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Emergence of a real-space symmetry axis in the magnetoresistance of the one-dimensional conductor Li_0.9Mo₆O₁₇.

Publications

Emergence of a real-space symmetry axis in the magnetoresistance of the one-dimensional conductor Li<sub>0.9</sub>Mo<sub>6</sub>O<sub>17</sub>.

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