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arXiv · 1009.2578

Highly Tunable Hybrid Quantum Dots with Charge Detection

C. Rössler·B. Küng·S. Dröscher·T. Choi·T. Ihn·K. Ensslin·M. Beck
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Abstract

In order to employ solid state quantum dots as qubits, both a high degree of control over the confinement potential as well as sensitive charge detection are essential. We demonstrate that by combining local anodic oxidation with local Schottky-gates, these criteria are nicely fulfilled in the resulting hybrid device. To this end, a quantum dot with adjacent charge detector is defined. After tuning the quantum dot to contain only a single electron, we are able to observe the charge detector signal of the quantum dot state for a wide range of tunnel couplings.

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C. Rössler, B. Küng, S. Dröscher, T. Choi, T. Ihn, K. Ensslin, M. Beck. 2010-09-14. Highly Tunable Hybrid Quantum Dots with Charge Detection. https://doi.org/10.1063/1.3501977

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