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


Using high resolution electron spectroscopy scientists from AIST and T. Pichler directly determined the local optical conductivity of a nanoscale semiconductor and their modification at individual defects. This paves the way to understand defect-related behaviors of e.g. excitons in optoelectronics.

Measurements of optical properties at a nanometer level are extremely important but challenging using conventional light-probes. In a recent publication in Nano Letters a co-operation between scientists from AIST in Japan led by Ryosuke Senga and Kazu Suenaga and Thomas Pichler determined the absolute local optical conductivity at the gap transitions of a nanoscale semiconductor with separated defects using high resolution electron energy-loss spectroscopy as probe. This opens up a new ability to assign defect-related excitonic behaviors in semiconductors in optoelectronic devices, such as light-emitting diodes or solar cells and will be a crucial tool to optimize their performance.

Nano Lett., DOI: 10.1021/acs.nanolett.8b01284