Seminars Archive
Optical manipulation of charge density waves
Abstract
Wednesday, April 30, 2003, 14:30
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
Optical manipulation of charge density waves
Paul van Loosdrecht
( University of Groningen, Laboratory of Solid State Physics,the
Netherlands)
Abstract
Electron-phonon interactions in low dimensional metals generally induce
a metal-insultor transition into a modulated charge density wave (CDW)
state. The fundamental excitations of the CDW are collective oscillations
of the phase (phasons) and amplitude (amplitudons) of the modulation.
It will be shown that one can optically manipulate the coherence of the
CDW. In particular, transient transport experiments on blue bronze,
performed at the FELIX free electron laser facility, show that the induced
CDW coherence leads to large temporal oscillations in the highly non linear
transport properties of the CDW state. In addition, femtosecond pump-probe
experiments are used to study the coherent excitation of amplitudons and
phonons in the CDW state of this material.
