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THz-spectroscopy

Projektbeschreibung:
Picosecond electromagnetic pulses in the far infrared are generated by short (12-100 fs) laser pulses in suitable electro-optic or photoconductive antennas, and propagated through an optical setup in the laboratory. The amplitude and phase of this pulse are explicitly measured. Transmission through a sample leads to distortion and delay of the pulse, and from these changes in pulse shape we extract the real and imaginary part of the refractive index of the sample at frequencies between 0.1 and 5 THz. The short pulsed fields are also suitable to give a Rydberg electron a momentum kick, to persuade a large biomolecule to undergo torsional vibrations, or to induce phonon-like modes in molecular and ionic crystals. The THz frequency range is relatively unexplored so far, but we have a unique tool to access it. Slow vibrational modes in a biomolecule are sensitive to secondary and tertiary structure of the molecule. With this in mind we hope to develop our spectroscopy systems into a useful tool in biomedicine. We also use pulsed THz technology to study carrier dynamics in quantum well and quantum dot nanostructures.

Ansprechpartner: Walter M
Tel: 0761/2037606
Email: markus.walther@physik.uni-freiburg.de
Projektlaufzeit:
Projektbeginn: 15.05.2006
Projektende: (unbegrenzt)
Projektleitung:
Walther M

Albert-Ludwigs-Universität Freiburg

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