Hou, H., Chung, Y., Rughoobur, G. et al. (7 more authors) (2018) Experimental verification of electrostatic boundary conditions in gate-patterned quantum devices. Journal of Physics D: Applied Physics, 51 (24). 244004. ISSN 0022-3727
Abstract
In a model of a gate-patterned quantum device, it is important to choose the correct electrostatic boundary conditions (BCs) in order to match experiment. In this study, we model gated-patterned devices in doped and undoped GaAs heterostructures for a variety of BCs. The best match is obtained for an unconstrained surface between the gates, with a dielectric region above it and a frozen layer of surface charge, together with a very deep back boundary. Experimentally, we find a ~0.2 V offset in pinch-off characteristics of 1D channels in a doped heterostructure before and after etching off a ZnO overlayer, as predicted by the model. Also, we observe a clear quantised current driven by a surface acoustic wave through a lateral induced n-i-n junction in an undoped heterostructure. In the model, the ability to pump electrons in this type of device is highly sensitive to the back BC. Using the improved boundary conditions, it is straightforward to model quantum devices quite accurately using standard software.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2018 IOP Publishing Ltd. This is an author produced version of a paper subsequently published in Journal of Physics D: Applied Physics. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | boundary condition; surface acoustic wave; patterned quantum device |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Electronic and Electrical Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 24 Oct 2018 13:29 |
Last Modified: | 24 May 2019 00:43 |
Published Version: | https://doi.org/10.1088/1361-6463/aac376 |
Status: | Published |
Publisher: | IOP Publishing |
Refereed: | Yes |
Identification Number: | 10.1088/1361-6463/aac376 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:137719 |