Molecular Circuits for Optoelectronics utilizing Carbon Nanotubes

Prof. Dr. Alexander W. Holleitner, Technische Universität München [Homepage]

Dr. Itai Carmeli, Tel-Aviv University [Homepage]

Prof. Dr. Friedrich Simmel, Technische Universität München [Homepage]

The optoelectronic quantum transport properties of molecular circuits consisting of
carbon nanotubes and single molecules or proteins shall be studied as a function of the
photon wavelength, the source/drain voltage, and the temperature in the range of 4.2 K
and room temperature. The proteins and molecules shall be contacted by carbon
nanotubes (CNTs), which act as mesoscopic source/drain contacts, via a self-assembly
process. The circuits “CNT-molecule-CNT” have a length of several hundreds of
nanometers, which allows contacting the circuits by standard focused ion-beam and ebeam
lithography. A particular emphasis shall be placed upon the optoelectronic
characterization of circuits containing metalloproteins such as the photosynthetic
reaction center “photosystem I”. For the photoexcitation of the organic circuits we utilize
a pulsed, wavelength-tunable laser system, which allows measuring the
photoconductance close to the absorption bands of the molecules and the carbon
nanotubes. Atomic rearrangements in the CNT-molecule (or CNT-protein) contact
region are expected to play only a minor role as compared to metal contacts. The aim of
the project is to exploit the outstanding optoelectronic properties of metalloproteins,
such as the photosystem I, found only in the photosynthetic systems for molecular
electronics.