405 citations · 2.8k across the 23 of their papers we have counts for
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Surface versus bulk state in topological insulator Bi2Se3 under environmental disorder
Matthew Brahlek, Yong Seung Kim, Namrata Bansal +2
Topological insulators (TIs) are predicted to be composed of an insulating bulk state along with conducting channels on the boundary of the material. In Bi2Se3, however, the Fermi…
Simple self-gettering differential-pump for minimizing source oxidation in oxide-MBE environment
Yong-Seung Kim, Namrata Bansal, Seongshik Oh
Source oxidation of easily oxidizing elements such as Ca, Sr, Ba, and Ti in an oxidizing ambient leads to their flux instability and is one of the biggest problems in the multi-ele…
Thickness-dependent bulk properties and weak anti-localization effect in topological insulator Bi2Se3
Yong Seung Kim, Matthew Brahlek, Namrata Bansal +7
We show that a number of transport properties in topological insulator (TI) Bi2Se3 exhibit striking thickness-dependences over a range of up to five orders of thickness (3 nm - 170…
Epitaxial growth of topological insulator Bi2Se3 film on Si(111) with atomically sharp interface
Namrata Bansal, Yong Seung Kim, Eliav Edrey +10
Atomically sharp epitaxial growth of Bi2Se3 films is achieved on Si (111) substrate with MBE (Molecular Beam Epitaxy). Two-step growth process is found to be a key to achieve inter…
Crucible aperture: an effective way to reduce source oxidation in oxide molecular beam epitaxy process
Yong-Seung Kim, Namrata Bansal, Seongshik Oh
Growing multi-elemental complex-oxide structures using an MBE (Molecular Beam Epitaxy) technique requires precise control of each source flux. However, when the component elements…
Sr flux stability against oxidation in oxide-MBE environment: flux, geometry, and pressure dependence
Y. S. Kim, Namrata Bansal, Carlos Chaparro +2
Maintaining stable fluxes for multiple source elements is a challenging task when the source materials have significantly different oxygen affinities in a complex-oxide molecular-b…
Thickness-independent transport channels in topological insulator Bi2Se3 thin films
Namrata Bansal, Yong Seung Kim, Matthew Brahlek +2
With high quality topological insulator (TI) Bi2Se3 thin films, we report thickness-independent transport properties over wide thickness ranges. Conductance remained nominally cons…
Metal-insulator transition on SrTiO surface induced by ionic-bombardment
Heiko Gross, Namrata Bansal, Yong-Seung Kim +1
SrTiO is one of the most popular insulating single-crystal substrates for various complex-oxide thin film growths, because of its good lattice match with many complex oxide f…