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arXiv · 1808.04847

Ultrafast time-resolved x-ray scattering reveals diffusive charge order dynamics in La$_{2-x}$Ba$_x$CuO$_4$

Matteo Mitrano·Sangjun Lee·Ali A. Husain·Luca Delacretaz·Minhui Zhu·Gilberto de la Peña Munoz·Stella Sun·Young Il Joe·Alexander H. Reid·Scott F. Wandel·Giacomo Coslovich·William Schlotter·Tim van Driel·John Schneeloch·Genda D. Gu·Sean Hartnoll·Nigel Goldenfeld·Peter Abbamonte
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Abstract

Charge order is universal among high-T$_c$ cuprates but its relevance to superconductivity is not established. It is widely believed that, while static order competes with superconductivity, dynamic order may be favorable and even contribute to Cooper pairing. We use time-resolved resonant soft x-ray scattering to study the collective dynamics of the charge order in the prototypical cuprate, La$_{2-x}$Ba$_x$CuO$_4$. We find that, at energy scales $0.4$ meV $ \lesssim \omega \lesssim 2$ meV, the excitations are overdamped and propagate via Brownian-like diffusion. At energy scales below 0.4 meV the charge order exhibits dynamic critical scaling, displaying universal behavior arising from propagation of topological defects. Our study implies that charge order is dynamic, so may participate tangibly in superconductivity.

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Matteo Mitrano, Sangjun Lee, Ali A. Husain, Luca Delacretaz, Minhui Zhu, Gilberto de la Peña Munoz, Stella Sun, Young Il Joe, Alexander H. Reid, Scott F. Wandel, Giacomo Coslovich, William Schlotter, Tim van Driel, John Schneeloch, Genda D. Gu, Sean Hartnoll, Nigel Goldenfeld, Peter Abbamonte. 2018-08-14. Ultrafast time-resolved x-ray scattering reveals diffusive charge order dynamics in La$_{2-x}$Ba$_x$CuO$_4$. https://arxiv.org/abs/1808.04847

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