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Impact of the gate geometry on adiabatic charge pumping in InAs double quantum dots.

ABSTRACT: We compare the adiabatic quantized charge pumping performed in two types of InAs nanowire double quantum dots (DQDs), either with tunnel barriers defined by closely spaced narrow bottom gates, or by well-separated side gates. In the device with an array of bottom gates of 100 nm pitch and 10 μm lengths, the pump current is quantized only up to frequencies of a few MHz due to the strong capacitive coupling between the bottom gates. In contrast, in devices with well-separated side gates with reduced mutual gate capacitances, we find well-defined pump currents up to 30 MHz. Our experiments demonstrate that high frequency quantized charge pumping requires careful optimization of the device geometry, including the typically neglected gate feed lines.

SUBMITTER: An SJ

PROVIDER: S-EPMC9470037 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Impact of the gate geometry on adiabatic charge pumping in InAs double quantum dots.

An Sung Jin SJ Bae Myung-Ho MH Lee Myoung-Jae MJ Song Man Suk MS Madsen Morten H MH Nygård Jesper J Schönenberger Christian C Baumgartner Andreas A Seo Jungpil J Jung Minkyung M

Nanoscale advances 20220811 18

We compare the adiabatic quantized charge pumping performed in two types of InAs nanowire double quantum dots (DQDs), either with tunnel barriers defined by closely spaced narrow bottom gates, or by well-separated side gates. In the device with an array of bottom gates of 100 nm pitch and 10 μm lengths, the pump current is quantized only up to frequencies of a few MHz due to the strong capacitive coupling between the bottom gates. In contrast, in devices with well-separated side gates with reduc ...[more]

PMID: 36133323

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Dataset Information

Impact of the gate geometry on adiabatic charge pumping in InAs double quantum dots.

Publications

Impact of the gate geometry on adiabatic charge pumping in InAs double quantum dots.

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