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Updated: Feb 22, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Optically Discriminating Carrier-Induced Quasiparticle Band Gap and Exciton Energy Renormalization in Monolayer
Kaiyuan Yao1,2, Aiming Yan3,4, Salman Kahn3
1Molecular Foundry Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Abstract:
Optoelectronic excitations in monolayer MoS_{2} manifest from a hierarchy of electrically tunable, Coulombic free-carrier and excitonic many-body phenomena. Investigating the fundamental interactions underpinning these phenomena-critical to both many-body physics exploration and device applications-presents challenges, however, due to a complex balance of competing optoelectronic effects and interdependent properties. Here, optical detection of bound- and free-carrier photoexcitations is used to directly quantify carrier-induced changes of the quasiparticle band gap and exciton binding energies. The results explicitly disentangle the competing effects and highlight longstanding theoretical predictions of large carrier-induced band gap and exciton renormalization in two-dimensional semiconductors.
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