Enhancement of transition temperature in Fe{sub x}Se{sub 0.5}Te{sub 0.5} film via iron vacancies
- Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 211189 (China)
- Australian Centre for Microscopy and Microanalysis, University of Sydney, Sydney, New South Wales 2006 (Australia)
- Institute for Superconducting and Electronic Materials, University of Wollongong, North Wollongong, New South Wales 2500 (Australia)
The effects of iron deficiency in Fe{sub x}Se{sub 0.5}Te{sub 0.5} thin films (0.8 ≤ x ≤ 1) on superconductivity and electronic properties have been studied. A significant enhancement of the superconducting transition temperature (T{sub C}) up to 21 K was observed in the most Fe deficient film (x = 0.8). Based on the observed and simulated structural variation results, there is a high possibility that Fe vacancies can be formed in the Fe{sub x}Se{sub 0.5}Te{sub 0.5} films. The enhancement of T{sub C} shows a strong relationship with the lattice strain effect induced by Fe vacancies. Importantly, the presence of Fe vacancies alters the charge carrier population by introducing electron charge carriers, with the Fe deficient film showing more metallic behavior than the defect-free film. Our study provides a means to enhance the superconductivity and tune the charge carriers via Fe vacancy, with no reliance on chemical doping.
- OSTI ID:
- 22303898
- Journal Information:
- Applied Physics Letters, Vol. 104, Issue 26; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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