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The magnetic-field–tuned superconductor-to-insulator transition was studied in a hybrid system of superconducting indium islands, deposited on an indium oxide (InOx) thin film, which exhibits global superconductivity at low magnetic fields. Vacuum annealing was used to tune the conductivity of the InOx film, thereby tuning the inergrain coupling and the nature of the transition. The hybrid system exhibits a “giant” magnetoresistance above the magnetic-field–tuned superconductor-to-insulator transition (H-SIT), with critical behavior similar to that of uniform InOx films but at much lower magnetic fields, that manifests the duality between Cooper pairs and vortices. A key feature of this hybrid system is the separation between the quantum criticality and the onset of nonequilibrium behavior.
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Superconductivity in Tin Telluride Films Grown by Molecular Beam Epitaxy
Abstract The intersection of superconductivity and ferroelectricity hosts a wide range of exotic quantum phenomena. Here, we report on the observation of superconductivity in high-quality tin telluride films grown by molecular beam epitaxy. Unintentionally doped tin telluride undergoes a ferroelectric transition at ~100 K. The critical temperature of superconductivity increases monotonically with indium concentration. The critical field of superconductivity, however, does not follow the same behavior as critical temperature with indium concentration and exhibits a carrier-density-dependent violation of the Pauli limit. The electron–phonon coupling, according to the McMillan formula, exhibits a systematic enhancement with indium concentration, suggesting a potential violation of Bardeen–Cooper–Schrieffer (BCS) weak coupling at high indium concentrations.
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- Award ID(s):
- 2122147
- PAR ID:
- 10586266
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Journal of Electronic Materials
- Volume:
- 54
- Issue:
- 7
- ISSN:
- 0361-5235
- Format(s):
- Medium: X Size: p. 5792-5799
- Size(s):
- p. 5792-5799
- Sponsoring Org:
- National Science Foundation
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