Photocurrent imaging of semiconducting carbon nanotube devices with local mirrors. Issue 12 (18th September 2014)

• Record Type: Journal Article
• Authors: Alam, Asiful; Flavel, Benjamin S.; Dehm, Simone; Lemmer, Uli; Krupke, Ralph
• Is Part Of: Physica status solidi. Volume 251:Issue 12(2014:Dec.)
• Page Start: 2471
• Page End: 2474
• Publication Date: 2014-09-18
• Subjects: Solid state physics -- Periodicals; Solids -- Periodicals; Atomic structure -- Periodicals; 530.41
• DOI: 10.1002/pssb.201451272
• Languages: English
• ISSNs: 0370-1972

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="pssb201451272-sec-0001" sec-type="section"> <p>Photocurrent spectroscopy has recently been used by several research groups to study the light–matter interaction in carbon nanotubes. To achieve this, long‐channel devices with symmetric metallic contacts are typically used, where photocurrent of opposite sign is generated at the two contacts. However, in short‐channel devices (&lt;1 µm) the diffraction‐limited laser spot results in simultaneous excitation of both metal–nanotube contacts and leads to partial cancellation of the photocurrent. In this work, we avoid simultaneous excitation of both metal–nanotube contacts by fabricating an isolated metallic mirror over one of the contacts. With the use of (6, 5) carbon nanotubes we demonstrate a unipolar photocurrent signal, that is consistent with the second order interband absorption of a (6, 5) nanotube.</p> </sec> </abstract>