Related Experiment Video
Updated: May 5, 2026
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Microstructural Engineering via Fe Deficiency in Fe(Se, Te) Superconductors: A Pathway to Enhanced Vortex Pinning
Qiao Sun1, Chiheng Dong1,2,3, Zhongtang Xu1,2,3
1Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China.
Small (Weinheim an Der Bergstrasse, Germany)
|May 4, 2026
Summary
Defect engineering in iron selenide telluride superconductors by introducing iron deficiency enhances flux pinning. This strategy improves critical current density and flux pinning forces, crucial for high-field applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Superconductivity
Background:
- Defect engineering optimizes material properties by controlling structural imperfections.
- Type-II superconductors benefit from defect-induced flux pinning centers, enhancing critical current density.
- Fe(Se, Te) is a key material for superconducting applications, but its flux pinning needs improvement.
Purpose of the Study:
- To engineer the microstructure of polycrystalline Fe(Se, Te) using strategic Fe deficiency.
- To investigate the impact of Fe deficiency on flux pinning mechanisms and superconducting properties.
- To demonstrate a method for enhancing high-field flux pinning in Fe(Se, Te) superconductors.
Main Methods:
- Microstructure engineering via controlled Fe deficiency in Fe(Se, Te).
- Analysis of nanoscale defect formation (Fe7(Se, Te)8) within the superconducting matrix.
- Characterization of flux pinning forces and critical current density (Jc) at elevated temperatures.
Main Results:
- Fe deficiency promotes the formation of nanoscale Fe7(Se, Te)8 defects, strengthening point pinning.
- Reduced interstitial Fe restores intrinsic Δκ pinning by minimizing Se/Te compositional fluctuations.
- Fe-deficient Fe(Se, Te) shows enhanced high-field flux pinning, evidenced by second magnetization peaks, higher Jc, and pinning forces.
Conclusions:
- Strategic Fe deficiency effectively engineers beneficial pinning centers in Fe(Se, Te) superconductors.
- This approach enhances high-field flux pinning and critical current density at elevated temperatures.
- The study provides guidance for improving flux pinning in type-II superconductors for high-field applications.
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