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Title: Highly Tunable Relaxors Developed from Antiferroelectrics
Abstract Highly responsive, voltage‐tunable dielectrics are essential for microwave‐telecommunication electronics. Ferroelectric/relaxor materials have been leading candidates for such functionality and have exhibited agile dielectric responses. Here, it is demonstrated that relaxor materials developed from antiferroelectrics can achieve both ultrahigh dielectric response and tunability. The system, based on alloying the archetypal antiferroelectric PbZrO3with the dielectric BaZrO3, exhibits a more complex phase evolution than that in traditional relaxors and is characterized by an unconventional multi‐phase competition between antiferroelectric, ferroelectric, and paraelectric order. This interplay of phases can greatly enhance the local heterogeneities and results in relaxor characteristics while preserving considerable polarizability. Upon studying Pb1‐xBaxZrO3forx= 0‐0.45, Pb0.65Ba0.35ZrO3is found to provide for exceptional dielectric tunability under low bias fields (≈81% at 200 kV cm−1and ≈91% at 500 kV cm−1) at 10 kHz, outcompeting most traditional relaxor ferroelectric films. This high tunability is sustained in the radio‐frequency range, resulting in a high commutation quality factor (>2000 at 1 GHz). This work highlights the phase evolution from antiferroelectrics (with lower, “positive” dielectric tunability) to relaxors (with higher, “negative” tunability), underscoring a promising approach to develop relaxors with enhanced functional capabilities and new possibilities.  more » « less
Award ID(s):
2329111
PAR ID:
10632480
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Materials
Volume:
37
Issue:
32
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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