Post Doctoral Fellowships

Highly competitive Compensation.

Prof. I. Sigalas. 27 11 717 7502
e-mail: iakovos.Sigalas@wits.ac.za

We seek an outstanding and preferably recent doctoral student in experimental (materials) physics for a post-doctoral fellowship in the School of Physics at the University of the Witwatersrand, Johannesburg, South Africa. Because of its strong tradition of high-level research it has recently received generous funding to establish various Centers of Excellence, one being in the field of Strong Materials. This School of Physics is considered one of the most accredited institutions for earning a post-graduate degree in physics on the African continent, and has good connections with many other internationally renowned academic institutes [http://www.wits.ac.za].

Work under this fellowship involves synthesis of aligned nanotubes and nanowires by employing pulsed (excimer) laser vaporization technique, characterization using nanoscopic-measurement tools and develop (opto-) electronics. An objective of this our project is to investigate (i) the synthesis mechanism of carbon nanotubes (ii) the microscopic origin of quantum confinement in semiconductor nanowires and also by applying high pressure (iii) high speed electrical conductance in 1D materials.

For synthesis we are establishing a facility for pulsed Excimer laser with other members of the School of Physics and National Laser Centre and will prepare carbon nanotubes and nanowires of Si, Ge, Si-Ge mixture and Ge-As, SiC which will also be doped and functionalized. In future nanowires of indium-oxide, ZnO, G s, GaN, SiGe, SiC, other nano-crystalline materials and superlattice of amorphous carbon will be synthesized as a part of the program.

For nano-characterization we routinely use a number of state of the art instruments including, micro-Raman (JY T64000 triple spectrograph), HRTEM (with EELS), Focused Ion Beam (with TEM), multimode AFM, Bruker D8 Advance powder diffractometer (up to 2000K), and other techniques for synthesis. Major experimental studies will include Raman spectroscopy, photoluminescence to study phonon confinement and Quantum confinement of carriers in the nanowires [see Appl. Phys. Lett. 84, 1564 (2004); Appl. Phys. Lett. 85, 2008 (2004)]. Collaborating with the Centre of Excellence of Strong Materials we shall be studying the effect of high pressure (up to 30 GPa) over a wide range of temperature (4K ? 2000 K) of various nano-materials.

For nanowire-based electronics we are developing a low-temperature research laboratory and will perform measurements down to 1K (or lower) and at a high field using a fully automated cryogen-free cryostat. For electrical characterization self assembled nanowires will be deposited on predefined substrates. These studies combined with optical measurements can lead to some optoelectronic devices. We also work in close collaboration both with neighboring universities in our city and with premier national research institutes in near proximity and internationally. In so doing we also have access to a range of other materials characterization tools and other carbon based devices.

The candidate required for this fellowship should have a high level of practical skills in experiments particularly in synthesis using laser-assisted or related techniques, spectroscopic measurements. The fellowship is available for two years. Applicants can send a CV including contact details of at least two referees to:
Prof. S. Bhattacharyya
e-mail: Somnath.Bhattacharyya@wits.ac.za

We seek an outstanding and preferably recent doctoral student in experimental (materials) physics for a post-doctoral fellowship in the School of Physics and for the Center of Excellence in Strong Materials who will work on quantum & high speed conductance at low temperatures/high magnetic field of carbon Quantum Well (QW) structures, nano-diamond, carbon nantubes. We are also looking for a candidate who will work on the synthesis of semiconductor nanowires and related nano-structured materials using pulsed laser ablation & (hot filament) CVD. Other potentially exciting projects that can be initiated so as to involve close colleagues within our School include: modeling of materials structure and calculating electronic structures, pressure tuning of electronic properties in novel carbon nano-structures (and other semiconductor quantum wells, nano-materials) and in situ Raman spectroscopy, carbon based quantum information and various characterization. We also work in close collaboration both with neighboring universities in our city and with premier national research institutes in near proximity and internationally and have access to a range of other materials characterization tools.

The candidate required for this fellowship should have a high level of practical skills, sufficient knowledge of electronic structure and electronic properties of materials. Prior experience in electrical transport measurements and/or materials synthesis and characterisation is desired. Applicants can send a CV including contact details of at least two referees to: Prof. S. Bhattacharyya