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Title: Tailoring excitonic states of van der Waals bilayers through stacking configuration, band alignment, and valley spin
Excitons in monolayer semiconductors have a large optical transition dipole for strong coupling with light. Interlayer excitons in heterobilayers feature a large electric dipole that enables strong coupling with an electric field and exciton-exciton interaction at the cost of a small optical dipole. We demonstrate the ability to create a new class of excitons in hetero- and homobilayers that combines advantages of monolayer and interlayer excitons, i.e., featuring both large optical and electric dipoles. These excitons consist of an electron confined in an individual layer, and a hole extended in both layers, where the carrier-species–dependent layer hybridization can be controlled through rotational, translational, band offset, and valley-spin degrees of freedom. We observe different species of layer-hybridized valley excitons, which can be used for realizing strongly interacting polaritonic gases and optical quantum controls of bidirectional interlayer carrier transfer.  more » « less
Award ID(s):
1808751 1720595
PAR ID:
10188528
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
5
Issue:
12
ISSN:
2375-2548
Page Range / eLocation ID:
eaax7407
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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