Direct Proof of a Defect-Modulated Gap Transition in Semiconducting Nanotubes

Author(s)
Ryosuke Senga, Thomas Pichler, Yohei Yomogida, Takeshi Tanaka, Hiromichi Kataura, Kazu Suenaga
Abstract

Measurements of optical properties at a nanometer level are of central importance for the characterization of optoelectronic devices. It is, however, difficult to use conventional light-probe measurements to determine the local optical properties from a single quantum object with nanometrical inhomogeneity. Here, we successfully measured the optical gap transitions of an individual semiconducting carbon nanotube with defects by using a monochromated electron source as a probe. The optical conductivity extracted from an electron energy-loss spectrum for a certain type of defect presents a characteristic modification near the lowest excitation peak (E-11), where excitons and nonradiative transitions, as well as phonon-coupled excitations, are strongly involved. Detailed line-shape analysis of the E-11 peak clearly shows different degrees of exciton lifetime shortening and electronic state modification according to the defect type.

Organisation(s)
Electronic Properties of Materials
External organisation(s)
National Institute of Advanced Industrial Science and Technology (AIST)
Journal
Nano Letters: a journal dedicated to nanoscience and nanotechnology
Volume
18
Pages
3920-3925
No. of pages
6
ISSN
1530-6984
DOI
https://doi.org/10.1021/acs.nanolett.8b01284
Publication date
06-2018
Peer reviewed
Yes
Austrian Fields of Science 2012
Materials physics, Nanomaterials
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/direct-proof-of-a-defectmodulated-gap-transition-in-semiconducting-nanotubes(3b4fd8ce-13bd-4504-8f38-b272903d9fd4).html