%0 Journal Article
%A Mankowsky, Roman
%A Först, M.
%A Loew, T.
%A Porras, J.
%A Keimer, B.
%A Cavalleri, A.
%T Coherent modulation of the YBa<sub>2</sub>Cu<sub>3</sub>O<sub>6+x</sub> atomic structure by displacive stimulated ionic Raman scattering
%J Physical review / B
%V 91
%N 9
%@ 1098-0121
%C College Park, Md.
%I APS
%M PUBDB-2016-03117
%P 094308
%D 2015
%X We discuss the mechanism of coherent phonon generation by stimulated ionic Raman scattering, a processdifferent from conventional excitation with near visible optical pulses. Ionic Raman scattering is driven byanharmonic coupling between a directly excited infrared-active phonon mode and other Raman modes. Weexperimentally study the response of YBa <sub>2</sub>Cu<sub>3</sub>O<sub>6+x</sub> to the resonant excitation of apical oxygen motions at 20 THzby midinfrared pulses, which has been shown in the past to enhance the interlayer superconducting coupling. Wefind coherent oscillations of four totally symmetric (A<sub>g</sub>) Raman modes and make a critical assessment of the roleof these oscillatory motions in the enhancement of superconductivity.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000352059700002
%R 10.1103/PhysRevB.91.094308
%U https://bib-pubdb1.desy.de/record/302074