Ultra-strong nonlinear optical processes and trigonal warping in MoS2 layers

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Antti Säynätjoki
  • Lasse Karvonen
  • Habib Rostami
  • Anton Autere
  • Soroush Mehravar
  • Antonio Lombardo
  • Robert A. Norwood
  • Tawfique Hasan
  • Nasser Peyghambarian
  • Harri Lipsanen

  • Khanh Kieu
  • Andrea C. Ferrari
  • Marco Polini
  • Zhipei Sun

Research units

  • University of Eastern Finland
  • Italian Institute of Technology
  • University of Arizona
  • University of Cambridge

Abstract

Nonlinear optical processes, such as harmonic generation, are of great interest for various applications, e.g., microscopy, therapy, and frequency conversion. However, high-order harmonic conversion is typically much less efficient than low-order, due to the weak intrinsic response of the higher-order nonlinear processes. Here we report ultra-strong optical nonlinearities in monolayer MoS2 (1L-MoS2): the third harmonic is 30 times stronger than the second, and the fourth is comparable to the second. The third harmonic generation efficiency for 1L-MoS2 is approximately three times higher than that for graphene, which was reported to have a large χ (3). We explain this by calculating the nonlinear response functions of 1L-MoS2 with a continuum-model Hamiltonian and quantum mechanical diagrammatic perturbation theory, highlighting the role of trigonal warping. A similar effect is expected in all other transition-metal dichalcogenides. Our results pave the way for efficient harmonic generation based on layered materials for applications such as microscopy and imaging.

Details

Original languageEnglish
Article number893
JournalNature Communications
Volume8
Issue number1
Publication statusPublished - 1 Dec 2017
MoE publication typeA1 Journal article-refereed

Download statistics

No data available

ID: 15868889