Cooper-Pair Spin Current in a Strontium Ruthenate Heterostructure.

Area of Science:

• Condensed Matter Physics
• Superconductivity
• Spintronics

Background:

• Spin-triplet Cooper pair condensation requires broken gauge symmetry and spin ordering.
• Spin-triplet superconductors may exhibit Cooper-pair spin currents, similar to magnon spin currents in magnetic insulators.
• The dynamics of spin-triplet superconductors can be subject to Gilbert damping.

Purpose of the Study:

• To explore the potential of a SrRuO3/Sr2RuO4 heterostructure for generating and controlling spin currents.
• To investigate the realization of long-range spin valves using this heterostructure.
• To demonstrate electrical driving of collective spin modes in spin-triplet superconductors.

Main Methods:

• Fabrication of a heterostructure with a thin film of the itinerant ferromagnet SrRuO3 on bulk Sr2RuO4.
• Theoretical analysis of spin transport properties within the heterostructure.
• Proposal for electrical manipulation of the spin-triplet order parameter.

Main Results:

• The SrRuO3/Sr2RuO4 heterostructure enables the creation of a long-range spin valve.
• The heterostructure allows for electrical driving of the collective spin mode of the spin-triplet order parameter.
• This system provides a novel platform for superfluid spin transport.

Conclusions:

• The proposed heterostructure is a promising system for experimental realization of superfluid spin transport.
• The study offers a new transport signature for identifying spin-triplet superconductivity.
• This work bridges spintronics and superconductivity research.