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Bulk superconductivity in bismuth oxysulfide Bi4O4S3
Shiva Kumar Singh1, Anuj Kumar, Bhasker Gahtori
1Quantum Phenomena and Applications Division, National Physical Laboratory (CSIR), Dr. K. S. Krishnan Road, New Delhi 110012, India.
Journal of the American Chemical Society
|September 26, 2012
Summary
We synthesized Bi(4)O(4)S(3) and confirmed it is a bulk superconductor with a transition temperature of 4.4 K. This discovery excludes impurity-driven superconductivity, opening new avenues for layered sulfide research.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid-State Chemistry
Background:
- Recent reports suggest superconductivity in layered sulfides.
- Bi(4)O(4)S(3) is a potential candidate for superconductivity research.
Purpose of the Study:
- Synthesize Bi(4)O(4)S(3) using a vacuum encapsulation technique.
- Characterize its superconducting properties.
- Investigate the origin of superconductivity.
Main Methods:
- Vacuum encapsulation synthesis at 500 °C.
- AC/DC magnetization measurements.
- Isothermal magnetization (M-H) and magnetotransport measurements.
Main Results:
- Synthesized Bi(4)O(4)S(3) with tetragonal structure (I4/mmm).
- Confirmed bulk superconductivity with a transition temperature (T(c)) of 4.4 K.
- Determined lower critical field (H(c1)) ~15 Oe and upper critical field (H(c2)(0)) ~31 kOe.
Conclusions:
- Bi(4)O(4)S(3) exhibits bulk superconductivity, not driven by impurities.
- The findings support further exploration of layered sulfides for superconductivity.
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