Charge Density Wave Activated Excitons in MoSe2

Published

January 5, 2022

Author(s)

Jaydeep Joshi, Benedikt Scharf, Igor Mazin, Sergiy Krylyuk, Daniel Campbell, Albert Davydov, Johnpierre Paglione, Igor Zutic, Patrick Vora

Abstract

Layered materials enable the assembly of a new class of heterostructures where lattice-matching is no longer a requirement. Interfaces in these heterostructures therefore become a fertile ground for new physics as dissimilar phenomena can be coupled via proximity effects. In this article we identify an unexpected photoluminescence (PL) peak when MoSe2 interacts with TiSe2. A series of temperature-dependent and spatially-resolved PL measurements reveal this peak is unique to the TiSe2 - MoSe2 interface, higher in energy compared to the neutral exciton, and exhibits exciton-like characteristics. The feature disappears at the TiSe2 charge density wave transition, suggesting that the density wave plays an important role in the formation of this new exciton. We present several plausible scenarios regarding the origin of this peak that individually capture some aspects of our observations but cannot fully explain this feature. These results therefore represent a fresh challenge for the theoretical community and provide a fascinating new way to engineer excitons through interactions with charge density waves.

Citation

APL Materials

Volume

10

Issue

1

Pub Type

Journals

Download Paper

https://doi.org/10.1063/5.0067098

Local Download

Keywords

2D materials, heterostructures, excitons

Citation

Joshi, J. , Scharf, B. , Mazin, I. , Krylyuk, S. , Campbell, D. , Davydov, A. , Paglione, J. , Zutic, I. and Vora, P. (2022), Charge Density Wave Activated Excitons in MoSe2, APL Materials, [online], https://doi.org/10.1063/5.0067098, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=933130 (Accessed October 14, 2025)