Topological insulator quantum dot with tunable barriers

Sungjae Cho; Dohun Kim; Paul Syers; Nicholas P. Butch; Johnpierre Paglione; Michael S. Fuhrer

doi:10.1021/nl203851g

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arXiv · 1201.3910

Topological insulator quantum dot with tunable barriers

Sungjae Cho·Dohun Kim·Paul Syers·Nicholas P. Butch·Johnpierre Paglione·Michael S. Fuhrer

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Abstract

Thin (6-7 quintuple layer) topological insulator Bi2Se3 quantum dot devices are demonstrated using ultrathin (2~4 quintuple layer) Bi2Se3 regions to realize semiconducting barriers which may be tuned from Ohmic to tunneling conduction via gate voltage. Transport spectroscopy shows Coulomb blockade with large charging energy >5 meV, with additional features implying excited states.

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Sungjae Cho, Dohun Kim, Paul Syers, Nicholas P. Butch, Johnpierre Paglione, Michael S. Fuhrer. 2012-01-18. Topological insulator quantum dot with tunable barriers. https://doi.org/10.1021/nl203851g

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