Superconductivity with high upper critical field in Ta-Hf alloys
POSTER
Abstract
Recently, there has been considerable interest in exploring superconducting alloys for potential applications in superconducting devices [1-3]. In this study, I will present our findings on superconductivity in Ta x Hf 1-x alloys, utilizing magnetization, electrical resistivity, and specific heat measurements on polycrystalline samples [3].
The crystal structures of these alloys are composition dependent. Notably, when we substituted Hf (a Type-I superconductor with a critical temperature, TC, of 0.12 K) with Ta (also a Type-I superconductor with a TC of 4.4 K), a remarkable enhancement in TC was observed, along with a transition to Type-II superconductivity featuring high upper-critical fields. This transition is of particular interest from the perspective of materials science. Our specific heat measurements provided evidence of strong coupling superconductivity, aligning with conventional principles of superconductivity. These metallic alloys exhibit both metallic properties and a high upper-critical field, making them highly promising for practical superconducting devices like SQUIDs and qubits.
The crystal structures of these alloys are composition dependent. Notably, when we substituted Hf (a Type-I superconductor with a critical temperature, TC, of 0.12 K) with Ta (also a Type-I superconductor with a TC of 4.4 K), a remarkable enhancement in TC was observed, along with a transition to Type-II superconductivity featuring high upper-critical fields. This transition is of particular interest from the perspective of materials science. Our specific heat measurements provided evidence of strong coupling superconductivity, aligning with conventional principles of superconductivity. These metallic alloys exhibit both metallic properties and a high upper-critical field, making them highly promising for practical superconducting devices like SQUIDs and qubits.
* We acknowledge Science and Engineering Research Board, Government of India for the financial support and we also thank CSIR, Government of India, for providing the SRF fellowship.
Publication: 1. T. G. Berlincourt et al. Phys. Rev. 131, 140 (1963).
2. J. K. Hulm et al. Phys. Rev. 123, 1569 (1961).
3. K. M. Wong et al. Phys. Rev. B 30, 1253 (1984).
4. A. P. Place et al. Nat. Commun. 12, 1779 (2021).
5. P. K. Meena et al. Phys. Rev. Materials 7, 084801 (2023).
Presenters
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Pavan K Meena
Indian Institute of Science Education and Research Bhopal, Indian Institute of Science Education and Research, Bhopal
Authors
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Pavan K Meena
Indian Institute of Science Education and Research Bhopal, Indian Institute of Science Education and Research, Bhopal