Partner 10. Freiburg University (ALU-FR)

Physikalisches Institut, Albert-Ludwigs-Universität Freiburg
Hermann-Herder-Strasse 3, D-79104 Freiburg, Germany

Scientific team

Name   Position   Task
Peter Uhd Jepsen (PUJ) Assistant Professor   THz-Team leader
Hanspeter Helm (HH) Full Professor   Department leader
Matthias Hoffmann (MH) Ph.D. Student   Development of new THz technology
Bernd Fischer (BF) Ph.D. Student   THz spectroscopy of small biomolecular systems
Markus Walther (MW) Ph.D. Student   THz spectroscopy of large biomolecules
Dmitry Turchinovich (DT)   Ph.D. Student   Time-resolved THz spectroscopy of semiconductors
Ulrich Person (UP) Technician   Construction and handling of vacuum equipment
Isabella Siegel (IS) Technician   Technical and electronic support

A post-doc position will be funded by the THz-BRIDGE project in collaboration with the UFRANK group. PUJ is leader of the THz group at ALU-FR. HH, PUJ, MH, BF, and MW will contribute to the THz-BRIDGE project.

Objectives and links to other participants

The group in Freiburg already has good collaboration with the partner USTUTT on spectroscopic investigations of sugars in the frequency range 0.05 - 4 THz. During the last 12 months of the THz-BRIDGE project this collaboration will continue. We collaborate with the partner at ENEA Frascati and ICEmB on the main topic of research, spectroscopic characterization of lymphocytes. A Ph.D. student will be seconded by the partner UFRANK to carry out this work in Freiburg.

Workplan

With the experience on far-infrared spectroscopy of biological systems, the group in Freiburg will contribute to the project workpackage 1 (WP-1) as described below.
The group will perform a spectral characterization of the main constituents of whole blood (serum, lymphocytes, white and red blood cells), in the form of isolated samples. This information will be used by the partner ENEA Frascati to refine SAR values for whole blood and its constituents. Samples will be prepared with assistance from the blood bank at the University Hospital in Freiburg, in accordance with protocols developed by the partner ICEmB.
Additionally, dielectric spectra of biomolecules in the THz range, recorded in Freiburg, will be made available to the public database which is currently being set up within the framework of the THz-BRIDGE project.


Allocated human resources:

Ph.D. student seconded by UFRANK         12 months
PUJ:         2 months
BF:         1 month
MH:         1 month
MW:         1 month
Technicians:         1 month
          -----------------
Total:         18 months

Deliverables

ALU-FR will contribute to the following deliverables:
Deliv. N. Deliverable title

Deliv.
date

Nature

Dissemination
level

D-12 Database of relevant frequencies to provide high contrast in imaging applications

24

R

RE

D-15 Report on spectral assignment to molecular structures

36

R

PU

D-16 Review of spectroscopy measurements in the THz region - Update of databases

36

R

PU


Background expertise and equipment available

The group in Freiburg has been pioneering in the development and refinement of terahertz time-domain spectroscopy since 1992. With an accumulated experience exceeding 30 man-years, the group has large expertise in spectroscopy of a wide range of materials in the far infrared. The group uses two different commercial femtosecond laser systems (a low-power oscillator and a regenerative amplifier system) to operate two THz time-domain spectrometers. The laboratories are fully equipped with modern optical and electronic equipment required to operate the systems in the most efficient manner. The requested funding from the THz-BRIDGE project will be used as partial support to set up a third spectrometer, thereby increasing the productivity significantly.

Since 2000 the group has been active in investigations of far-infrared properties of biological systems. Special emphasis has so far been on obtaining a better understanding of the basic physical mechanisms leading to distinct absorption features in large organic systems in the far infrared, such as intermolecular hydrogen bonding and low-energy interactions such as van der Waals forces and dispersion interactions.


References
M. Walther, B. M. Fischer & P. U. Jepsen, "Noncovalent intermolecular forces in polycrystalline and amorphous saccharides in the far infrared", Chem. Phys. 288, 269 (2003).

B. M. Fischer, M. Walther & P. U. Jepsen, "Far-infrared vibrational modes of DNA components studied by terahertz time-domain spectroscopy", Phys. Med. Biol. 47, 3807 (2002)

M. Walther, P. Plochocka, B. Fischer, H. Helm, and P. U. Jepsen, "Collective vibrational modes in biological molecules investigated by terahertz time-domain spectroscopy", Biospectroscopy (Biopolymers) 67, 310 (2002)

M. Walther, B. Fischer, M. Schall, H. Helm & P. U. Jepsen, "Far-infrared vibrational spectra of all-trans, 9-cis and 13-cis retinal measured by THz time-domain spectroscopy", Chem. Phys. Lett. 332, 389 (2000).

M. Schall, M. Walther, and P. Uhd Jepsen, "Fundamental and second-order phonon processes in CdTe and ZnTe", Phys. Rev. B 64, 094301 (2001).