Superconductivity beyond the Conventional Pauli Limit in High-Pressure CeSb_{2}

Area of Science:

• Condensed Matter Physics
• Quantum Materials
• Superconductivity Research

Background:

• Kondo lattice systems exhibit complex magnetic and electronic properties.
• Quantum phase transitions (QPTs) can dramatically alter material states.
• Superconductivity near magnetic QPTs is a key area of research.

Purpose of the Study:

• To investigate the emergence of superconductivity in CeSb2 under pressure.
• To explore the behavior of superconductivity in high magnetic fields.
• To understand the relationship between magnetic QPTs and superconductivity in this system.

Main Methods:

• Applying hydrostatic pressure to CeSb2 samples.
• Inducing and observing magnetic quantum phase transitions.
• Measuring superconducting properties and critical fields.

Main Results:

• Superconductivity was discovered at a pressure-induced magnetic QPT in CeSb2.
• The superconducting state was sustained at magnetic fields eight times higher than the Pauli limit.
• Noncentrosymmetric local structure around the Ce site was noted, similar to CeRh2As2.

Conclusions:

• The findings suggest a novel mechanism for high-field superconductivity in CeSb2.
• The resilience of superconductivity challenges existing theoretical frameworks.
• Further research is needed to elucidate the unique properties of CeSb2.