Pressure-Induced Superconductivity up to 9 K in the Quasi-One-Dimensional KMn_{6}Bi_{5}

Area of Science:

• Condensed Matter Physics
• Materials Science
• Superconductivity

Background:

• Manganese-based superconductors are rare due to strong magnetic pair-breaking effects.
• Antiferromagnetic metals present challenges for achieving superconductivity.

Purpose of the Study:

• To investigate pressure-induced superconductivity in KMn$_{6}$Bi$_{5}$.
• To explore the relationship between magnetism and superconductivity in this material.

Main Methods:

• Electrical resistance and AC magnetic susceptibility measurements.
• Hydrostatic pressure application up to 14.2 GPa using a cubic anvil cell.

Main Results:

• KMn$_{6}$Bi$_{5}$ is an antiferromagnetic metal at ambient pressure (T$_{N}$≈75 K).
• Superconductivity emerges near a critical pressure (P$_{c}$≈13 GPa) with a maximum T$_{c}^{onset}$ of 9.3 K at 14 GPa.
• The superconducting dome and large upper critical field suggest an unconventional magnetism-mediated pairing mechanism.

Conclusions:

• KMn$_{6}$Bi$_{5}$ is the first ternary manganese-based superconductor, discovered under pressure.
• The proximity of superconductivity to magnetic instability indicates unconventional pairing.
• The ternary AMn$_{6}$Bi$_{5}$ system offers potential for discovering new manganese-based superconductors.