Studies on the proximity effect in Bi-based high temperature superconductor/manganite heterostructures
Gayathri V1,2, E P Amaladass1,2, A T Sathyanarayana1,2
1Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, India. mani@igcar.gov.in.
Physical Chemistry Chemical Physics : PCCP
|April 17, 2025
Summary
Researchers studied superconductor/ferromagnet heterostructures, finding that stacking order controls electronic properties. This proximity effect enables a colossal-magnetoresistance ratio of 99%, advancing spintronics and interfacial engineering.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Investigating heterostructures of high-temperature cuprate superconductors and ferromagnetic manganites is crucial for understanding emergent electronic phenomena.
- The interplay between superconductivity and magnetism at interfaces can lead to novel physical properties and device applications.
Purpose of the Study:
- To elucidate the heterostructures of Bi-based cuprate superconductors and Pr-based ferromagnetic manganites.
- To investigate the effect of magnetic proximity on superconductivity and vice versa.
- To explore the role of synthesis sequence and interfacial properties on the electronic behavior of superconductor/ferromagnet junctions.
Main Methods:
- Structural and elemental characterization using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS).
- Magnetotransport and magnetization measurements to probe superconductivity and magnetism.
- Analysis of electronic properties considering synthesis sequence, interface morphology, crystallinity, and interfacial interactions.
Main Results:
- Established the influence of ferromagnetic proximity on superconductivity in Bi1.75Pb0.25Sr2Ca2Cu3O10+/Pr0.6Sr0.4MnO3 heterostructures.
- Demonstrated that the stacking sequence dictates the ground state properties, enabling a transformation from superconducting to ferromagnetic behavior.
- Observed proximity-induced changes rationalized by magnetic exchange interaction, Cooper-pair leakage, and spin-polarized electron transport.
- Achieved a colossal-magnetoresistance (CMR) ratio of approximately 99% due to the proximity effect.
Conclusions:
- The stacking order of layers in superconductor/ferromagnet heterostructures is a critical parameter for controlling electronic properties.
- Proximity effects significantly influence the interplay between superconductivity and magnetism, leading to tunable electronic states.
- These findings pave the way for advancements in spintronics and interfacial engineering, with potential for technological applications leveraging the observed CMR effect.
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