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arXiv · 1812.04978

Thickness dependence of electron-electron interactions in topological p-n junctions

Dirk Backes·Danhong Huang·Rhodri Mansell·Martin Lanius·Jörn Kampmeier·David Ritchie·Gregor Mussler·Godfrey Gumbs·Detlev Grützmacher·Vijay Narayan
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Abstract

Electron-electron interactions in topological p-n junctions consisting of vertically stacked topological insulators are investigated. n-type Bi2Te3 and p-type Sb2Te3 of varying relative thicknesses are deposited using molecular beam epitaxy and their electronic properties measured using low-temperature transport. The screening factor is observed to decrease with increasing sample thickness, a finding which is corroborated by semi-classical Boltzmann theory. The number of two-dimensional states determined from electron-electron interactions is larger compared to the number obtained from weak-antilocalization, in line with earlier experiments using single layers.

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Dirk Backes, Danhong Huang, Rhodri Mansell, Martin Lanius, Jörn Kampmeier, David Ritchie, Gregor Mussler, Godfrey Gumbs, Detlev Grützmacher, Vijay Narayan. 2018-12-12. Thickness dependence of electron-electron interactions in topological p-n junctions. https://doi.org/10.1103/physrevb.99.125139

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