Linsheng Liu

Crystal Phase Quantum Dots

In semiconducting nanowires, both zinc blende and wurtzite crystal structures can coexist. The band structure difference between the two structures can lead to charge confinement. Here we fabricate and study single quantum dot devices defined solely by crystal phase in a chemically homogeneous nanowire and observe single photon generation. More generally, our results show that this type of carrier confinement represents a novel degree of freedom in device design at the nanoscale.

Wurtzite GaAs/AlGaAs core–shell nanowires grown by molecular beam epitaxy

We report the growth of GaAs/AlGaAs core-shell nanowires (NWs) on GaAs(111)B substrates by Au-assisted molecular beam epitaxy. Electron microscopy shows the formation of a wurtzite AlGaAs shell structure both in the radial and the axial directions outside a wurtzite GaAs core. With higher Al content, a lower axial and a higher radial growth rate of the AlGaAs shell were observed. Room temperature and low temperature (4.4 K) micro-photoluminescence measurements show a much higher radiative efficiency from the GaAs core after the NW is overgrown with a radial AlGaAs shell.

Advances in III-V Semiconductor Nanowires and Nanodevices

Description: Semiconductor nanowires exhibit novel electronic and optical properties due to their unique onedimensional structure and quantum confinement effects. In particular, III-V semiconductor nanowires have been of great scientific and technological interest for next generation optoelectronic devices including transistors, light emitting diodes, lasers, photodetectors, and solar cells. Advances in III-V Semiconductor Nanowires and Nanodevices is an account of recent progress in the synthesis, characterization, physical properties, device fabrication, and applications of binary compound and ternary alloy III-V semiconductor nanowires. Each chapter is prepared by renowned experts in the field, describing the current state of knowledge and key areas of research. The book is written at the expert level, but also serves as a guide for researchers or graduate students aiming to enter semiconductor research.