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arXiv · 1712.00820

Optically discriminating carrier-induced quasiparticle band gap and exciton energy renormalization in monolayer MoS2

Kaiyuan Yao·Aiming Yan·Salman Kahn·Aslihan Suslu·Yufeng Liang·Edward S. Barnard·Sefaattin Tongay·Alex Zettl·Nicholas J. Borys·P. James Schuck
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Abstract

Optoelectronic excitations in monolayer MoS2 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 2D semiconductors.

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Kaiyuan Yao, Aiming Yan, Salman Kahn, Aslihan Suslu, Yufeng Liang, Edward S. Barnard, Sefaattin Tongay, Alex Zettl, Nicholas J. Borys, P. James Schuck. 2017-12-03. Optically discriminating carrier-induced quasiparticle band gap and exciton energy renormalization in monolayer MoS2. https://doi.org/10.1103/physrevlett.119.087401

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