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Title: Engineering interfacial polarization switching in van der Waals multilayers
In conventional ferroelectric materials, polarization is an intrinsic property limited by bulk crystallographic structure and symmetry. Recently, it has been demonstrated that polar order can also be accessed using inherently non-polar van der Waals materials through layer-by-layer assembly into heterostructures, wherein interfacial interactions can generate spontaneous, switchable polarization. Here, we show that deliberate interlayer rotations in multilayer vdW heterostructures modulate both the spatial ordering and switching dy- namics of polar domains. The engendered tunability is unparalleled in conventional bulk ferroelectrics or polar bilayers. By means of operando transmission electron microscopy we show how alterations of the relative rotations of three WSe2 layers produce structural poly- types with distinct arrangements of polar domains with either a global or localized switching response. Furthermore, the presence of uniaxial strain generates structural anisotropy that yields a range of switching behaviors, coercivities, and even tunable biased responses. We also provide evidence of mechanical coupling between the two interfaces of the trilayer, a key consideration for the control of switching dynamics in polar multilayer structures more broadly.  more » « less
Award ID(s):
2238196
PAR ID:
10569766
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Springer Nature
Date Published:
Journal Name:
Nature Nanotechnology
Volume:
19
Issue:
6
ISSN:
1748-3387
Page Range / eLocation ID:
751 to 757
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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