Modifying the band gap and optical properties of Germanium nanowires by surface termination

Show simple item record

dc.contributor.author Legesse, Merid
dc.contributor.author Fagas, Gíorgos
dc.contributor.author Nolan, Michael
dc.date.accessioned 2016-11-22T09:41:25Z
dc.date.available 2016-11-22T09:41:25Z
dc.date.issued 2016-11-15
dc.identifier.citation Legesse, M., Fagas, G. & Nolan, M. ‘Modifying the band gap and optical properties of Germanium nanowires by surface termination’, Applied Surface Science. In Press. doi: 10.1016/j.apsusc.2016.11.104 en
dc.identifier.issn 0169-4332
dc.identifier.uri http://hdl.handle.net/10468/3299
dc.identifier.doi 10.1016/j.apsusc.2016.11.104
dc.description.abstract Semiconductor nanowires, based on silicon (Si) or germanium (Ge) are leading candidates for many ICT applications, including next generation transistors, optoelectronics, gas and biosensing and photovoltaics. Key to these applications is the possibility to tune the band gap by changing the diameter of the nanowire. Ge nanowires of different diameter have been studied with H termination, but, using ideas from chemistry, changing the surface terminating group can be used to modulate the band gap. In this paper we apply the generalised gradient approximation of density functional theory (GGA-DFT) and hybrid DFT to study the effect of diameter and surface termination using –H, –NH2 and –OH groups on the band gap of (001), (110) and (111) oriented germanium nanowires. We show that the surface terminating group allows both the magnitude and the nature of the band gap to be changed. We further show that the absorption edge shifts to longer wavelength with the –NH2 and –OH terminations compared to the –H termination and we trace the origin of this effect to valence band modifications upon modifying the nanowire with –NH2 or –OH. These results show that it is possible to tune the band gap of small diameter Ge nanowires over a range of ca. 1.1 eV by simple surface chemistry. en
dc.description.sponsorship Science Foundation Ireland (SFI Starting Investigator Research Grant Program, project EMOIN grant number SFI 09/SIRG/I1620) en
dc.format.mimetype application/pdf en
dc.language.iso en en
dc.publisher Elsevier en
dc.rights © 2016 Published by Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ en
dc.rights.uri http://creativecommons.org/licenses/by-nc-nd/4.0/ en
dc.subject Ge-nanowires en
dc.subject Bandgap en
dc.subject Surface termination en
dc.subject DFT en
dc.subject Adsoption en
dc.title Modifying the band gap and optical properties of Germanium nanowires by surface termination en
dc.type Article (peer-reviewed) en
dc.internal.authorcontactother Michael Nolan, Tyndall Theory Modelling & Design Centre, University College Cork, Cork, Ireland. +353-21-490-3000 Email: michael.nolan@tyndall.ie en
dc.internal.availability Full text available en
dc.check.info Access to this item is restricted until 24 months after publication by the request of the publisher en
dc.check.date 2018-11-15
dc.description.version Accepted Version en
dc.internal.rssid 372727876
dc.contributor.funder Science Foundation Ireland en
dc.contributor.funder European Commission en
dc.contributor.funder Seventh Framework Programme en
dc.description.status Peer reviewed en
dc.identifier.journaltitle Applied Surface Science en
dc.internal.copyrightchecked !!CORA!! en
dc.internal.bibliocheck In Press, Nov 2016. Update citation details and check embargo date, 24 months after publication en
dc.relation.project info:eu-repo/grantAgreement/EC/FP7::SP1::ICT/257856/EU/Semiconducting Nanowire Platform for Autonomous Sensors/SINAPS en


Files in this item

This item appears in the following Collection(s)

Show simple item record

© 2016 Published by Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ Except where otherwise noted, this item's license is described as © 2016 Published by Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
This website uses cookies. By using this website, you consent to the use of cookies in accordance with the UCC Privacy and Cookies Statement. For more information about cookies and how you can disable them, visit our Privacy and Cookies statement