Engineering | Scholarship for Nigerians and Africans - Part 165

PhD Position Fluorescence Lifetime Microscopy, IGSM, Germany: Metrology in Life Sciences

In bio and food sciences a maximum of information within a cell is required at a minimum of interference, i.e. in vivo research should be performed without disturbing natural processes. In addition, the observations should be quantitative and the gained quantities independent of the applied investigation technique.

We use one-color (1c2p) and two-color-two-photon (2c2p) excitation of laser dyes, NAD(P)H, tryptophan and unlabeled proteins upon excitation around 400 and 800nm using the SHG and fundamental wavelength of a mode locked Ti:Sa femtosecond laser.

In combination with fluorescence lifetime and polarisation measurements this technique is optimal for “in vivo” investigations due to its very good intrinsic 3D resolution, large penetration depth, and especially its independence of fluorescence intensities. Beside the detection of pH or pO2 values, index of diffraction n, or Ca2+ concentrations (with a resolution of 300nm), melanin, NAD(P)H and tryptophan can be directly observed. A discrimination between free and enzyme bound species is possible on a quantitative level without using any calibration procedure. Spores will be analyzed using this technique to get a better understanding of the underlying molecular processes of sporulation.

Scholarship Application Deadline:31 March 2011

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PhD Studentship in Ocean Biogeochemistry, MPI-M, Germany

The applicant will be part of the Research Group Ocean Biogeochemistry in the Department The Ocean in the Earth System. The research will focus on reconstructing the ocean carbon cycle and its interactions with climate during the Paleocene-Eocene Thermal Maximum. The main tool will be the existing Earth system model of the MPI-M, which includes the ocean biogeochemistry model HAMOCC. One of the objectives of the project will be to improve our understanding of the PETM and its potential to serve as an analogue of the future climate perturbations due to anthropogenic CO2 emissions.

Requirements: We are looking for a highly motivated individual with a M.Sc. or diploma in Geosciences, Oceanography, Environmental Sciences, Physics or a related field. Experience, or a strong interest in biogeochemistry and modeling is of advantage. Good programming skills (FORTRAN on Unix platforms) are desirable, since the applicant will use facilities of the high performance computing centre. The working language is English. The MPI-M encourages doctoral students to participate in the International Max Planck Research School on Earth System Modeling.

Scholarship Application Deadline: before 15th of March 2011

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Doctoral Scholarship in GaN-based Single Photon Emitters, Germany: Quantum Metrology

The interest in single-photon-emitters rises continuously since quantum communication based on the polarization of single photons has already been demonstrated. Unfortunately up to now almost all single-photon sources are pumped optically which makes the realization of a widespread communication network very complex.

For this reason it would be of great advantage to fabricate electrically pumped single-photon-sources. This can be realized e. g. by fabricating LED structures with active regions, where only single ions are incorporated, leading to single photon emission. The LEDs could be driven electrically and the optical energy of the LED is transferred to the single transition available in the active region of the LED. Today, only very few reports on electrical single photon sources are available.

Zinc is a very promising candidate as a single photon emitter in GaN based LEDs. Zn acceptors show efficient emission in the blue spectral range. Zn creates a deep acceptor level 0.3 eV – 0.4 eV above the valence band. Furthermore, Silicon-codoping is required for efficient optical emission, resulting in a very bright photo-luminescence at 2.9 eV (~ 430 nm) which has been assigned to donor-acceptor (DA) transitions.

The goal of this thesis is to investigate single transitions in GaN based LEDs with Zn and Si co-doping. LEDs will be fabricated by MOCVD and processed in house. A thorough analysis of the relevant optical transitions by time resolved optical characterization will allow to get information on the nature and characteristics of the transitions, as well as on the emission statistics in order to get a quantitative handle on the statistical quality of single photon emission correlated with that.

Scholarship Application Deadline: 31 March 2011

Further Scholarship Information and Application