Anisotropic electron phonon coupling in colloidal layered TiS2 nanodiscs observed via coherent acoustic phonons

Daniel Rossi, Luis E. Camacho Forero, Guadalupe Ramos Sánchez, Jae Hyo Han, Jinwoo Cheon, Perla Balbuena, Dong Hee Son

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Atomically thin layered transition metal dichalcogenides with highly anisotropic structure exhibit strong anisotropy in various material properties. Here, we report the anisotropic coupling between the interband optical transition and coherent acoustic phonon excited by ultrashort optical excitation in a colloidal solution of multilayered TiS2 nanodiscs. The transient absorption signal from the diameter and thickness controlled TiS2 nanodiscs dispersed in solution exhibited an oscillatory feature, which is attributed to the modulation of the interband absorption peak by the intralayer breathing mode. However, the signature of the interlayer acoustic phonon was not observed, while it has been previously observed in noncolloidal exfoliated sheets of MoS2. The dominance of the intralayer mode in modulating the interband optical transition was supported by the density functional theory (DFT) calculations of the optical absorption spectra of TiS2, which showed the stronger sensitivity of the interband absorption peak in the visible region to the in plane strain than to the out of plane strain.

Original languageEnglish
Pages (from-to)7436-7442
Number of pages7
JournalJournal of Physical Chemistry C
Volume119
Issue number13
DOIs
Publication statusPublished - 2015 Jan 1

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

Fingerprint Dive into the research topics of 'Anisotropic electron phonon coupling in colloidal layered TiS<sub>2</sub> nanodiscs observed via coherent acoustic phonons'. Together they form a unique fingerprint.

  • Cite this

    Rossi, D., Camacho Forero, L. E., Ramos Sánchez, G., Han, J. H., Cheon, J., Balbuena, P., & Son, D. H. (2015). Anisotropic electron phonon coupling in colloidal layered TiS2 nanodiscs observed via coherent acoustic phonons. Journal of Physical Chemistry C, 119(13), 7436-7442. https://doi.org/10.1021/jp512182j