UC San Diego

One-dimensional (1D) nanostructure has become one of the most exciting forefronts in nanotechnology fueled by demand for more compact and powerful devices that could affect people's lives in many aspects, from simple household appliances and multimedia systems to communications, computing and medical instruments. In particular, semiconductor nanowires (NWs) and/or nanotubes (NTs) are emerging among the most promising family of platforms since, through controlled chemical growth and specific fabrication, such semiconductor NWs and/or NTs can open up substantial opportunities for novel nanoscale devices, such as electronic devices, mechanical devices, thermoelectric devices, and pharmaceutical devices. In one aspect, understanding the unique nature of 1D electrical transport and the proposed enhancement in performance are crucial to the developments of the nanoscale electric device, mechanical device, or a combination hereof. Yet in another aspect, using the particular structure of the 1D semiconductor heterostructures to synthesize novel 1D nanostructures (e.g., NTs) may provide advantageous benefits to advanced pharmaceutical devices. This dissertation covers topics addressing both critical scientific areas of fundamental understanding of charge transport phenomena of Ge/Si core/shell heterostructure NWs and applications using the core/shell heterostructure NWs and single crystalline Si NTs