Direct coupling between magnetism and superconducting current in the Josephson phi0 junction.

Area of Science:

• Condensed Matter Physics
• Superconductivity
• Spintronics

Background:

• The proximity effect describes how superconductivity can be induced in a normal metal adjacent to a superconductor.
• Magnetic materials introduce complex interactions, particularly spin-orbit interactions, which can significantly alter superconducting properties.

Purpose of the Study:

• To investigate the Josephson junction properties between a conventional superconductor and a magnetic normal metal featuring Rashba spin-orbit interaction.
• To explore the formation of a finite phase difference (phi{0}) in the Josephson junction's ground state.

Main Methods:

• Utilized the phenomenological Ginzburg-Landau theory.
• Employed the quasiclassical Eilenberger approach for theoretical analysis.

Main Results:

• Demonstrated a special nonsinusoidal current-phase relation in the Josephson junction.
• Characterized the ground state by a finite phase difference (phi{0}).
• Showed phi{0} is proportional to spin-orbit interaction strength and exchange field.

Conclusions:

• The study establishes a direct coupling between superconducting current and magnetic moment in the weak link.
• Introduced a mechanism for forming phi{0} junctions.
• Highlighted the potential of phi{0} junctions for advancing superconducting spintronics.