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(In,Ga)As gated-vertical quantum dot with an Al2O3 insulator

Tomohiro Kita·Daichi Chiba·Yuzo Ohno·Hideo Ohno
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Abstract

We fabricated a gated-vertical (In,Ga)As quantum dot with an Al2O3 gate insulator deposited using atomic layer deposition and investigated its electrical transport properties at low temperatures. The gate voltage dependence of the dI/dV-V characteristics shows clear Coulomb diamonds at 1.1K. The metal-insulator gate structure allowed us to control the number of electrons in the quantum dot from 0 to a large number estimated to be about 130.

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Tomohiro Kita, Daichi Chiba, Yuzo Ohno, Hideo Ohno. 2007-01-03. (In,Ga)As gated-vertical quantum dot with an Al2O3 insulator. https://arxiv.org/abs/cond-mat/0701046

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