Fabrication of Semiconductor Nanowires for Electronic Transport Measurements

We report on epitaxial growth of InAs nanowires and the steps necessary to create devices for electrnic transport experiments. Growth conditions were found by the use of metal organic vapor phase epitaxy (MOVPE) resulting in nanowires with designable length and diameter. Electrical properties indicate diffusive electron transport with an elastic mean free path of around hundred nanometers. Coherent quantum mechanical effects and single electron tunneling can be observed at low temperatures in quantum dots created along the nanowire. We demonstrate the realization of highly tunable quantum dots with metallic top-gates. Beyond that, alternative techniques to introduce potential barriers based on local constrictions are investigated.