With recent technologies thin core-shell nanowires of 100 nm diameter or less, and length up to tens of μm, can be fabricated with semiconductors. Such a structure is made of a core of one material surrounded by a layer of another material, and can be seen as a radial version of the classical planar heterojunction. With an insulating core and a thin conductive shell one obtains a conductor with tubular geometry. In this presentation three types of electronic localization in tubular shells will be discussed, together with some of the physical consequences.
- The primary radial localization has consequences in magnetotransport. When travelling along the tube the electrons perform loops which generate conductance oscillations of Aharonov-Bohm nature.
- In a magnetic field perpendicular to the tube an angular localization develops along the directions lateral to the field, where so-called snaking orbits are created. In a magnetic field of a few Tesla the electronic current flows along these side regions.
- The cross section of bottom-up grown nanowires is usually polygonal, most often hexagonal, and the shell is a prismatic tube. The electrons with low energies tend to localize along the edges of the shell which thus becomes a collection of nanowires itself.
About The Speaker
Professor Manolescu is currently a Professor at Reykjavik University. He received his doctorate (1992) at the Institute of Atomic Physics, Bucharest after completing his M.S (1983) at University of Bucharest, Romania. His research interests lies with theoretical modelling and numerical calculations of quantum-mechanical electronic properties of semiconductor nanostructures as well as statistical analysis of human genetic data.
At present, he is involved in time dependent electronic transport in open nanosystems, charge polarization, and thermoelectric transport and partly involved in a project on genetic epidemiology of cancer in Romania. He has authored more than 200 papers in journals and proceedings of international conferences.