Tunable tunnel coupling in a double quantum antidot with cotunneling via localized state

Abstract

Controlling tunnel coupling between quantum antidots (QADs) in the quantum Hall (QH) regime is problematic. We propose and demonstrate a scheme for tunable tunnel coupling between two QADs by utilizing a cotunneling process via a localized state as a third QAD. The effective tunnel coupling can be tuned by changing the localized level even with constant nearest-neighbor tunnel couplings. We systematically study the variation of transport characteristics in the effectively triple QAD system at the Landau level filling factor $\nu =2$. The tunable tunnel coupling is clarified by analyzing the anti-crossing of Coulomb blockade peaks in the charge stability diagram, in agreement with numerical simulations based on the master equation. The scheme is attractive for studying coherence and interaction in QH systems.

11 pages, 8 figures

References in corpus (7)

• An electrostatically defined serial triple quantum dot charged with few electrons
• Aharonov-Bohm interference of fractional quantum Hall edge modes
• A triple quantum dot in a single wall carbon nanotube
• Electron interactions in an antidot in the integer quantum Hall regime
• Coherent transport in a linear triple quantum dot made from a pure-phase InAs nanowire
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