Inelastic photon scattering

We are currently studying lattice dynamics, electronic and magnetic excitations in various strongly correlated systems using inelastic scattering of photons (visible and x-ray) as our main tool. We focus more specifically on unconventional superconductivity in high-T_c cuprates as well as in the recently discovered iron-based superconductors, where we used inelastic photon scattering to probe various electronic phases of these rich systems. We are also interested in the interplay between magnetism and superconductivity in transition-metal-oxide heterostructures and superlattices (YBa₂Cu₃O_6+y and La_1−xCa_xMnO₃). This work aims at studying the consequences of orbital reconstructions at the interfaces on the lattice dynamical properties of these systems. These projects are carried out in close collaboration with other groups of our department.

Recent Publications Feedback effect on high-energy magnetic fluctuations in the model high-temperature superconductor HgBa2CuO4 + δ observed by electronic Raman scattering Yuan Li, M. Le Tacon, M. Bakr, D. Terrade, D. Manske, R. Hackl, L. Ji, M. K. Chan, N. Barišić, X. Zhao, M. Greven, B. Keimer. Preprint: arXiv:1112.2725 (to be published in Phys. Rev. Lett.) Anomalous dependence of the c-axis polarized Fe B1g phonon mode with Fe and Se concentrations in Fe1+yTe1-xSex Y. J. Um, A. Subedi, P. Toulemonde, A. Y. Ganin, L. Boeri, M. Rahlenbeck, Y. Liu, C. T. Lin, S. J. E. Carlsson, A. Sulpice, M. J. Rosseinsky, B. Keimer, M. Le Tacon. Phys. Rev. B 85 (2012), 064519 Raman Scattering Study of the Lattice Dynamics of Superconducting LiFeAs Y. J. Um, J. T. Park, S. H. Jung, Y. J. Song, Y. S. Kwon, B. Keimer, M. Le Tacon. Phys. Rev. B 85 (2012), 012501 Understanding the complex phase diagram of uranium: the role of electron-phonon coupling S. Raymond, J. Bouchet, G. H. Lander, M. Le Tacon, G. Garbarino, M. Hoesch, J.-P. Rueff, M. Krisch, J. C. Lashley, R. K. Schulze, R. C. Albers. Phys. Rev. Lett. 107 (2011), 136401 (featured on PRL's cover). Intense paramagnon excitations in a large family of high-temperature superconductors M. Le Tacon, G. Ghiringhelli, J. Chaloupka, M. Moretti Sala, V. Hinkov, M. W. Haverkort, M. Minola, M. Bakr, K. J. Zhou, S. Blanco-Canosa, C. Monney, Y. T. Song, G. L. Sun, C. T. Lin, G. M. De Luca, M. Salluzzo, G. Khaliullin, T. Schmitt, L. Braicovich, B. Keimer. Nature Physics 7 (2011), 725–730 Raman light scattering study and microstructural analysis of epitaxial films of the electron-doped superconductor La2−xCexCuO4 M. Rahlenbeck, M. Wagenknecht, A. Tsukada, D. Koelle, R. Kleiner, B. Keimer, C. Ulrich. Eur. Phys. J. B 75 (2010), 461–467 Inelastic x-ray scattering study of superconducting SmFeAsO1−xFy single crystals: Evidence for strong momentum-dependent doping-induced renormalizations of optical phonons M. Le Tacon, T. R. Forrest, Ch. Rüegg, A. Bosak, A. C. Walters, R. Mittal, H. M. Rønnow, N. D. Zhigadlo, S. Katrych, J. Karpinski, J. P. Hill, M. Krisch, D. F. McMorrow. Phys. Rev. B 80 (2009), 220504(R) Phonon anomalies in pure and underdoped R1−xKxFe2As2 (R = Ba, Sr) investigated by Raman light scattering M. Rahlenbeck, G. L. Sun, D. L. Sun, C. T. Lin, B. Keimer, C. Ulrich. Phys. Rev. B 80 (2009), 064509 Full list of publications...