Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Charge Density Wave Activated Excitons in MoSe2



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


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.
APL Materials


2D materials, heterostructures, excitons


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],, (Accessed June 23, 2024)


If you have any questions about this publication or are having problems accessing it, please contact

Created January 5, 2022, Updated November 29, 2022