Dielectric screening of excitons and trions in single-layer MoS2

Yuxuan Lin, Xi Ling, Lili Yu, Shengxi Huang, Allen L. Hsu, Yi Hsien Lee, Jing Kong, Mildred S. Dresselhaus, Tomás Palacios

Research output: Contribution to journalArticlepeer-review

518 Scopus citations


Photoluminescence (PL) properties of single-layer MoS2 are indicated to have strong correlations with the surrounding dielectric environment. Blue shifts of up to 40 meV of exciton or trion PL peaks were observed as a function of the dielectric constant of the environment. These results can be explained by the dielectric screening effect of the Coulomb potential; based on this, a scaling relationship was developed with the extracted electronic band gap and exciton and trion binding energies in good agreement with theoretical estimations. It was also observed that the trion/exciton intensity ratio can be tuned by at least 1 order of magnitude with different dielectric environments. Our findings are helpful to better understand the tightly bound exciton properties in strongly quantum-confined systems and provide a simple approach to the selective and separate generation of excitons or trions with potential applications in excitonic interconnects and valleytronics.

Original languageEnglish (US)
Pages (from-to)5569-5576
Number of pages8
JournalNano letters
Issue number10
StatePublished - Oct 8 2014

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • General Chemistry
  • General Materials Science
  • Condensed Matter Physics
  • Mechanical Engineering


Dive into the research topics of 'Dielectric screening of excitons and trions in single-layer MoS2'. Together they form a unique fingerprint.

Cite this