Multicomponent odd-parity superconductivity in UAu₂ at high pressure.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Materials

Background:

• Heavy fermion materials like uranium diauride (UAu2) exhibit complex electronic behaviors.
• Antiferromagnetic states in quantum materials can be sensitive to external stimuli like pressure.
• Understanding pressure-induced phase transitions is crucial for discovering novel quantum phenomena.

Purpose of the Study:

• To investigate the pressure-dependent phase diagram of uranium diauride (UAu2).
• To characterize the superconducting state emerging above the suppressed antiferromagnetic phase.
• To explore the potential of this superconducting state for applications in quantum computing.

Main Methods:

• High-pressure synthesis and characterization of single-crystal uranium diauride (UAu2).
• Resistivity measurements under varying pressures and magnetic fields.
• Analysis of critical magnetic field behavior and angular dependence.

Main Results:

• Superconductivity emerges in UAu2 above 3.2 GPa, coinciding with the suppression of an unusual antiferromagnetic state.
• The antiferromagnetic state exhibits marginal Fermi liquid behavior with non-standard resistivity evolution.
• The pressure-induced superconductivity is robust in high magnetic fields and displays anomalous angular dependence, suggesting a multi-component order parameter.

Conclusions:

• The observed superconductivity is likely linked to the suppression of the unique antiferromagnetic state.
• The multi-component order parameter predicts the existence of half-quantum vortices (HQVs).
• These half-quantum vortices offer potential for topological entanglement and advancements in quantum computing.