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Title: Interface Engineering for Enhanced Magnetic Vortex Pinning by 1D-BZO APCs in a Wide Angular Range
Abstract Microstructural analysis of the BaZrO 3 (BZO)/YBa 2 Cu 3 O 7 (YBCO) interface has revealed a highly defective and oxygen deficient 2-3 nm thick YBCO column surrounding the BZO one-dimensional artificial pinning centers (1D-APCs). The resulting semi-coherent interface is the consequence of the ∼7.7% BZO/YBCO lattice mismatch and is responsible for the low pinning efficiency of BZO 1D-APCs. Herein, we report an interface engineering approach of dynamic Ca/Cu replacement on YBCO lattice to reduce/eliminate the BZO/YBCO lattice mismatch for improved pinning at a wide angular range of the magnetic field orientation. The Ca/Cu replacement induces a local elongation of the YBCO c-lattice near the BZO/YBCO interface, thereby ensuring a reduction in the BZO/YBCO lattice mismatch to ∼1.4% and a coherent BZO/YBCO interface. This has resulted in enhanced pinning at B//c-axis and a broad angular range of B-field orientation. For example, the 6 vol.% BZO/YBCO film with interface engineering exhibits F p ∼158 GN/m 3 at 65 K and B//c-axis, which is 440% higher than the ∼36.1 GN/m 3 for the reference 6% BZO/YBCO sample, and enhanced J c and F p in a wide angular range up to ∼ 80°. This result illustrates a facile scheme for engineering 1D-APC/YBCO interface to resume the pristine pinning efficiency of the 1D-APCs.  more » « less
Award ID(s):
1809293 1909292
NSF-PAR ID:
10382726
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
IOP Conference Series: Materials Science and Engineering
Volume:
1241
Issue:
1
ISSN:
1757-8981
Page Range / eLocation ID:
012022
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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