Probing electronic order via coupling to low energy phonons in superconducting Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$

C. J. Bonnoit; D. R. Gardner; R. Chisnell; A. H. Said; Y. Okada; T. Kondo; T. Takeuchi; H. Ikuta; D. E. Moncton; Y. S. Lee

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arXiv · 1202.4994

Probing electronic order via coupling to low energy phonons in superconducting Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$

C. J. Bonnoit·D. R. Gardner·R. Chisnell·A. H. Said·Y. Okada·T. Kondo·T. Takeuchi·H. Ikuta·D. E. Moncton·Y. S. Lee

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Abstract

We report high-resolution inelastic x-ray scattering measurements of the acoustic phonons in the single-layer cuprate $Bi_{2}Sr_{2-x)La_{x}CuO_{6+\delta}$. These measurements reveal anomalous broadening of the longitudinal acoustic phonon near the (1/4,1/4,0) wavevector. The observed wavevector and its doping dependence indicate the coupling of the phonons to an underlying electronic density wave state. In addition, a comparison of the scattered intensities for x-ray energy-gain and x-ray energy-loss indicates that both time-reversal and inversion symmetries are broken in the material. Upon cooling, the effects of symmetry breaking are enhanced in the pseudogap state.

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C. J. Bonnoit, D. R. Gardner, R. Chisnell, A. H. Said, Y. Okada, T. Kondo, T. Takeuchi, H. Ikuta, D. E. Moncton, Y. S. Lee. 2012-02-22. Probing electronic order via coupling to low energy phonons in superconducting Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$. https://arxiv.org/abs/1202.4994

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