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Title: Optical generation of high carrier densities in 2D semiconductor heterobilayers
Controlling charge density in two-dimensional (2D) materials is a powerful approach for engineering new electronic phases and properties. This control is traditionally realized by electrostatic gating. Here, we report an optical approach for generation of high carrier densities using transition metal dichalcogenide heterobilayers, WSe 2 /MoSe 2 , with type II band alignment. By tuning the optical excitation density above the Mott threshold, we realize the phase transition from interlayer excitons to charge-separated electron/hole plasmas, where photoexcited electrons and holes are localized to individual layers. High carrier densities up to 4 × 10 14 cm −2 can be sustained under both pulsed and continuous wave excitation conditions. These findings open the door to optical control of electronic phases in 2D heterobilayers.  more » « less
Award ID(s):
1809680
PAR ID:
10155492
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
5
Issue:
9
ISSN:
2375-2548
Page Range / eLocation ID:
eaax0145
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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