Two-step growth of high quality Bi2Te3 thin films on Al2O3 (0001) by molecular beam epitaxy
APPLIED PHYSICS LETTERS 102:17 (2013) ARTN 171906
Weak localization effects as evidence for bulk quantization in Bi2Se3 thin films
PHYSICAL REVIEW B 88:12 (2013) ARTN 121103
Controlling the carriers of topological insulators by bulk and surface doping
Semiconductor Science and Technology 27:12 (2012)
Abstract:
We report a systematic study of bulk and surface chemical doping effects on single Dirac cone topological insulator Bi2Se3 and Bi2Te3. By bulk doping, we were able to achieve full range control of charge carrier types and concentration, with the exact Fermi energy measured by angle-resolved photoemission spectroscopy (ARPES). Due to the unusual robustness of the topological surface state, we further realized the bi-polar control of the surface carriers by gaseous or alkaline surface doping without affecting the topological nature of these materials. The doping progress monitored by in situ ARPES study clearly demonstrated the switching between different carrier types through the Dirac point. The ability to control the carrier types and the concentration of topological insulators will greatly facilitate future applications. © 2012 IOP Publishing Ltd.Controlled synthesis of topological insulator nanoplate arrays on mica
Journal of the American Chemical Society 134:14 (2012) 6132-6135
Abstract:
The orientation- and position-controlled synthesis of single-crystal topological insulator (Bi 2Se 3 and Bi 2Te 3) nanoplate arrays on mica substrates was achieved using van der Waals epitaxy. Individual ultrathin nanoplates with the lateral dimension up to ∼0.1 mm or uniform thickness down to 1-2 nm were produced. Single-Dirac-cone surface states of nanoplate aggregates were confirmed by angle-resolved photoemission spectroscopy measurements. The large-grain-size, single-crystal nanoplate arrays grown on mica can act as facile platforms for a combination of spectroscopy and in situ transport measurements, which may open up new avenues for studying exotic physical phenomena, surface chemical reactions, and modification in topological insulators. © 2012 American Chemical Society.Studies on the electronic structures of three-dimensional topological insulators by angle resolved photoemission spectroscopy
Frontiers of Physics 7:2 (2012) 175-192