[Press Release] Catching Excitons in Motion—Ultrafast Dynamics in Carbon Nanotubes Revealed by Nano-Infrared Spectroscopy

Release Summary

• Excitons—bound pairs of electrons and holes created by light—are key to the optoelectronic behavior of carbon nanotubes (CNTs). However, because excitons are confined to extremely small regions and exist for only fleeting moments, it has been extremely challenging to directly observe their behavior using conventional measurement techniques.
• In this study, we overcame that challenge by using an ultrafast infrared near-field optical microscope that focuses femtosecond infrared laser pulses down to the nanoscale. This advanced approach allowed us to visualize where excitons are generated and decay inside CNTs in real space and real time.
• Our observations revealed that nanoscale variations in the local environment—such as subtle lattice distortions within individual CNTs or interactions with neighboring CNTs—can significantly affect exciton generation and relaxation dynamics.
• These insights into local exciton dynamics pave the way for precise control of light-matter interactions at the nanoscale, offering new opportunities for the development of advanced optoelectronic devices and quantum technologies based on carbon nanotube platforms.

For Details (EurekAlert!)

• Journal: Science Advances
• Title: Ultrafast infrared nano-imaging of local electron-hole dynamics in CVD-grown single-walled carbon nanotubes
• Authors: Jun Nishida^＊, Keigo Otsuka, Taketoshi Minato, Yuichiro K. Kato, Takashi Kumagai^{＊
  ＊} Corresponding Authors
• DOI: 10.1126/sciadv.adv9584

• Institute for Molecular Science
• Molecular Science