DPG Phi
Verhandlungen
Verhandlungen
DPG

Dresden 2011 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 35: CE: Low-dimensional Systems - Materials 3

TT 35.12: Talk

Wednesday, March 16, 2011, 17:15–17:30, HSZ 301

Vibrational control of Mottness in the organic Mott insulator ET-F2TCNQStefan Kaiser1, •Daniele Nicoletti1, Raanan I. Tobey2, Nicky Dean2, Stefano Lupi3, Hiroshi Okamoto4, Jun'ya Tsutsumi4, Tatsuo Hasegawa4, and Andrea Cavalleri1,21Max Planck Research Department for Structural Dynamics, Center for Free Electron Laser Science & University of Hamburg, c/o DESY, Hamburg, Germany — 2Department of Physics, Oxford University, UK — 3Department of Physics, University of Rome La Sapienza, Italy — 4AIST, Tsukuba, Japan

Control of on-site electronic wavefunctions is achieved in the organic conductor ET-F2TCNQ by resonant excitation of localized vibrational modes of the ET molecule. Such excitation modulates the on-site Coulomb repulsion and modifies the relative strength of electron correlations and hopping, thus controlling the Mott criterion. We performed pump-probe experiments using optical parametrical amplifiers, with a time resolution of 80 fs. Excitation was achieved with mid-IR pulses from difference frequency mixing, resonant with two different intramolecular vibrations at 10 and 6 microns. The probe was tuned over the whole IR range, in order to trace the reflectivity changes in the charge-transfer band and the possible filling of the Mott gap, thus providing a direct evidence of the control of on-site Coulomb repulsion. Through such mode-selective excitations, the Mott gap can be filled and the system is pushed forward to the less correlated and metallic side. This approach promises a new way of control for electronic and even superconducting properties in correlated electron systems.

100% | Mobile Layout | Deutsche Version | Contact/Imprint/Privacy
DPG-Physik > DPG-Verhandlungen > 2011 > Dresden