Visualizing domain wall and reverse domain superconductivity

Area of Science:

• Condensed matter physics
• Materials science

Background:

• Magnetically coupled planar ferromagnet-superconductor (F/S) hybrid structures exhibit unique superconducting properties.
• Magnetic domain walls in these structures can spatially confine superconductivity.

Purpose of the Study:

• To directly image the nucleation of superconductivity at domain walls in F/S structures.
• To explore the control of superconducting properties via magnetic domain walls.

Main Methods:

• Utilized scanning tunnelling spectroscopy (STS).
• Fabricated F/S structures using Co-Pd multilayers and Pb thin films.

Main Results:

• Demonstrated spatial confinement of superconductivity by magnetic domain walls.
• Observed that superconducting nucleation is governed by inhomogeneous magnetic fields.
• Showcased control over superconducting nucleus strength and location using external magnetic fields.

Conclusions:

• F/S structures with magnetic domain walls serve as model systems for studying superconductivity control.
• These systems offer potential for guiding magnetic vortices in future computing applications.