Charge density waves in YBa$_2$Cu$_3$O$_{6.67}$ probed by resonant x-ray scattering under uniaxial compression

H. -H. Kim; E. Lefrançois; K. Kummer; R. Fumagalli; N. B. Brookes; D. Betto; S. Nakata; M. Tortora; J. Porras; T. Loew; M. Barber; L. Braicovich; A. P. Mackenzie; C. W. Hicks; B. Keimer; M. Minola; M. Le Tacon

doi:10.1103/physrevlett.126.037002

arXiv · 2009.00928

Charge density waves in YBa$_2$Cu$_3$O$_{6.67}$ probed by resonant x-ray scattering under uniaxial compression

H. -H. Kim·E. Lefrançois·K. Kummer·R. Fumagalli·N. B. Brookes·D. Betto·S. Nakata·M. Tortora·J. Porras·T. Loew·M. Barber·L. Braicovich·A. P. Mackenzie·C. W. Hicks·B. Keimer·M. Minola·M. Le Tacon

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Abstract

We report a comprehensive Cu L$_3$-edge resonant x-ray scattering study of two- and three-dimensional (2D and 3D) incommensurate charge correlations in single crystals of the underdoped high-temperature superconductor YBa$_2$Cu$_3$O$_{6.67}$ under uniaxial compression up to 1% along the two inequivalent Cu-O-Cu bond directions (a and b) in the CuO$_2$ planes. The pressure response of the 2D charge correlations is symmetric: pressure along a enhances correlations along b, and vice versa. Our results imply that the underlying order parameter is uniaxial. In contrast, 3D long-range charge order is only observed along b in response to compression along a. Spectroscopic resonant x-ray scattering measurements show that the 3D charge order resides exclusively in the CuO$_2$ planes and may thus be generic to the cuprates. We discuss implications of these results for models of electronic nematicity and for the interplay between charge order and superconductivity.

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H. -H. Kim, E. Lefrançois, K. Kummer, R. Fumagalli, N. B. Brookes, D. Betto, S. Nakata, M. Tortora, J. Porras, T. Loew, M. Barber, L. Braicovich, A. P. Mackenzie, C. W. Hicks, B. Keimer, M. Minola, M. Le Tacon. 2020-09-02. Charge density waves in YBa$_2$Cu$_3$O$_{6.67}$ probed by resonant x-ray scattering under uniaxial compression. https://doi.org/10.1103/physrevlett.126.037002

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