Title: Designing high-performance superconductors with nanoparticle inclusions: Comparisons to strong pinning theory

Abstract

One of the most promising routes for achieving high critical currents in superconductors is to incorporate dispersed, non-superconducting nanoparticles to control the dissipative motion of vortices. However, these inclusions reduce the overall superconducting volume and can strain the interlaying superconducting matrix, which can detrimentally reduce T_c. Consequently, an optimal balance must be achieved between the nanoparticle density n_p and size d. Determining this balance requires garnering a better understanding of vortex–nanoparticle interactions, described by strong pinning theory. Here, we map the dependence of the critical current on nanoparticle size and density in (Y_0.77, Gd_0.23)Ba₂Cu₃O_7-δ films in magnetic fields of up to 35 T and compare the trends to recent results from time-dependent Ginzburg–Landau simulations. We identify consistency between the field-dependent critical current J_c(B) and expectations from strong pinning theory. Specifically, we find that J_c ∝ B^-α, where α decreases from 0.66 to 0.2 with increasing density of nanoparticles and increases roughly linearly with nanoparticle size d/ξ (normalized to the coherence length). At high fields, the critical current decays faster (~B^-1), suggesting that each nanoparticle has captured a vortex. When nanoparticles capture more than one vortex, a small, high-field peak is expected in J_c(B). Due to a spread in defect sizes,more » this novel peak effect remains unresolved here. Finally, we reveal that the dependence of the vortex creep rate S on nanoparticle size and density roughly mirrors that of α, and we compare our results to low-T nonlinearities in S(T) that are predicted by strong pinning theory.« less

Authors:

Jones, Sarah C. ^[1]; Miura, Masashi  ^[2];

• Search DOE PAGES for author "Miura, Masashi"
• Search DOE PAGES for ORCID "0000-0002-9985-3622"

Yoshida, Ryuji ^[3]; Kato, Takeharu  ^[3];

• Search DOE PAGES for author "Kato, Takeharu"
• Search DOE PAGES for ORCID "0000-0002-2836-3095"

Civale, Leonardo  ^[4];

• Search DOE PAGES for author "Civale, Leonardo"
• Search DOE PAGES for ORCID "0000-0003-0806-3113"

Willa, Roland  ^[5];

• Search DOE PAGES for author "Willa, Roland"
• Search DOE PAGES for ORCID "0000-0003-1537-0824"

Eley, Serena  ^[1]

• Search DOE PAGES for author "Eley, Serena"
• Search DOE PAGES for ORCID "0000-0002-2928-5316"

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+ Show Author Affiliations

1. Colorado School of Mines, Golden, CO (United States)
2. Seikei Univ., Tokyo (Japan)
3. Japan Fine Ceramics Center, Nagoya (Japan). Nanostructures Research Lab.
4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
5. Heidelberger Akademie der Wissenschaften, Heidelberg (Germany); Karlsruhe Inst. of Technology (KIT) (Germany). Inst. for Theory of Condensed Matter

Publication Date:

Tue Sep 07 00:00:00 EDT 2021

Research Org.:

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:

USDOE Office of Science (SC). Office of Basic Energy Sciences (BES); National Science Foundation (NSF); German Research Foundation (DFG); JSPS KAKENHI; JST FOREST

OSTI Identifier:

1823760

Report Number(s):

LA-UR-21-27236
Journal ID: ISSN 2166-532X; TRN: US2216015

Grant/Contract Number:  

89233218CNA000001; DMR-1905909; DMR-1644779; 288-422213477; JPMJFR202G; 18KK0414; 20H02184

Resource Type:

Accepted Manuscript

Journal Name:

APL Materials

Additional Journal Information:

Journal Volume: 9; Journal Issue: 9; Journal ID: ISSN 2166-532X

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; High temperature superconductors, vortex pinning, critical currents, nanoparticles; Thin films; Superconductivity models; Vortex dynamics; Quantum vortices; Superconductors; Transmission electron microscopy; Crystal twinnings; Nanoparticles; Crystallographic defects