Temperature-dependent electron-phonon coupling in La$_{2-x}$Sr$_x$CuO$_4$ probed by femtosecond X-ray diffraction
Abstract
The strength of the electron-phonon coupling parameter and its evolution throughout a solid's phase diagram often determines phenomena such as superconductivity, charge- and spin-density waves. Its experimental determination relies on the ability to distinguish thermally activated phonons from those emitted by conduction band electrons, which can be achieved in an elegant way by ultrafast techniques. Separating the electronic from the out-of-equilibrium lattice subsystems, we probed their re-equilibration by monitoring the transient lattice temperature through femtosecond X-ray diffraction in LaSrCuO single crystals with =0.1 and 0.21. The temperature dependence of the electron-phonon coupling is obtained experimentally and shows similar trends to what is expected from the \textit{ab-initio} calculated shape of the electronic density-of-states near the Fermi energy. This study evidences the important role of band effects in the electron-lattice interaction in solids, in particular in superconductors.
Keywords
Cite
@article{arxiv.1401.4072,
title = {Temperature-dependent electron-phonon coupling in La$_{2-x}$Sr$_x$CuO$_4$ probed by femtosecond X-ray diffraction},
author = {B. Mansart and M. J. G. Cottet and G. F. Mancini and T. Jarlborg and S. B. Dugdale and S. L. Johnson and S. O. Mariager and C. J. Milne and P. Beaud and S. Grübel and J. A. Johnson and T. Kubacka and G. Ingold and K. Prsa and H. M. Rønnow and K. Conder and E. Pomjakushina and M. Chergui and F. Carbone},
journal= {arXiv preprint arXiv:1401.4072},
year = {2014}
}