Volume 110, Number 5, June 2015
|Number of page(s)||5|
|Section||Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties|
|Published online||19 June 2015|
Dirac electron-hole pairing gap in the heterostructure of ultra-thin films of topological insulator bilayer
Institute of Applied Physics and Computational Mathematics - P. O. Box 8009, Beijing 100088, China
Received: 24 April 2015
Accepted: 1 June 2015
The electron-hole pairing gap in a system of topological insulator (TI) ultra-thin film bilayer separated by a dielectric barrier is theoretically investigated beyond the mean-field approximation. We show that the pairing gap Δ is dramatically suppressed when accounting for the Coulomb correlation effect as well as the finite-thickness effect of the dielectric barrier. However, Δ can be increased by the coupling between the upper and lower surface states of each TI ultra-thin film. In order to observe much larger Δ in the present structure experimentally, the dielectric surrounding media materials with much lower dielectric constant, such as SiO2-based xerogel films, may be needed.
PACS: 71.35.-y – Excitons and related phenomena / 73.20.-r – Electron states at surfaces and interfaces / 73.22.Gk – Broken symmetry phases
© EPLA, 2015
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.