paper

Topological insulator homojunctions including magnetic layers: the example of n-p type ( $n$ -QLs Bi $_{2}$ Se $_{3}$ /Mn-Bi $_{2}$ Se $_{3}$ ) heterostructures

arXiv:1602.03450 · doi:10.1063/1.4954834

Abstract

Homojunctions between Bi $_{2}$ Se $_{3}$ and its Mn-doped phase are investigated as a sample geometry to study the influence of spin degrees of freedom on topological insulator properties. $n$ quintuple layers (QLs) of Bi $_{2}$ Se $_{3}$ are grown ontop of Mn-doped Bi $_{2}$ Se $_{3}$ by molecular beam epitaxy for $0 \leq n \leq 30$ QLs, allowing to unhamperedly monitor the development of electronic and topological properties by surface sensitive techniques like angle resolved photoemission spectroscopy. With increasing $n$ , a Mn-induced gap at the Dirac point is gradually filled in an "hourglass" fashion to reestablish a topological surface state at $n \sim 9$ QLs. Our results suggest a competition of upwards and downwards band bending effects due to the presence of an n-p type interface, which can be used to tailor topological and quantum well states independently.

5 pages, 5 figures

Topological insulator homojunctions including magnetic layers: the example of n-p type (n-QLs Bi2​Se3​/Mn-Bi2​Se3​) heterostructures

Abstract

Topological insulator homojunctions including magnetic layers: the example of n-p type ( $n$ -QLs Bi $_{2}$ Se $_{3}$ /Mn-Bi $_{2}$ Se $_{3}$ ) heterostructures