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Title: Spontaneous Supercrystal Formation During a Strain‐Engineered Metal–Insulator Transition
Abstract Mott metal–insulator transitions possess electronic, magnetic, and structural degrees of freedom promising next‐generation energy‐efficient electronics. A previously unknown, hierarchically ordered, and anisotropic supercrystal state is reported and its intrinsic formation characterized in‐situ during a Mott transition in a Ca2RuO4thin film. Machine learning‐assisted X‐ray nanodiffraction together with cryogenic electron microscopy reveal multi‐scale periodic domain formation at and below the film transition temperature (TFilm ≈ 200–250 K) and a separate anisotropic spatial structure at and aboveTFilm. Local resistivity measurements imply an intrinsic coupling of the supercrystal orientation to the material's anisotropic conductivity. These findings add a new degree of complexity to the physical understanding of Mott transitions, opening opportunities for designing materials with tunable electronic properties.  more » « less
Award ID(s):
2011839 1719875 2104427 2039380
PAR ID:
10541055
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Materials
Volume:
36
Issue:
32
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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