Discovery of the Pt-Based Superconductor LaPt5As

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid-State Chemistry

Background:

• Superconductivity is a quantum mechanical phenomenon observed in certain materials below a critical temperature.
• The discovery of new superconducting materials is crucial for advancing technologies like energy transmission and magnetic resonance imaging.
• High-pressure synthesis is a powerful technique for stabilizing novel material phases that are inaccessible under ambient conditions.

Purpose of the Study:

• To discover and characterize a novel superconducting material synthesized under high pressure.
• To investigate the relationship between crystal structure, synthesis pressure, and superconducting properties of the new material.
• To explore the potential of high-pressure synthesis for discovering new phases in materials.

Main Methods:

• High-pressure synthesis using a Kawai-type apparatus.
• Crystal structure characterization.
• Superconducting transition temperature (Tc) measurements.
• Density functional theory (DFT) calculations.

Main Results:

• A new superconductor, LaPt5As, was discovered with a superconducting transition temperature (Tc) of 2.6 K.
• LaPt5As exhibits a unique crystal structure with a long c lattice parameter (>60 Å) and network-like Pt layers.
• Single-phase superconducting LaPt5As was obtained at a sintering pressure of approximately 10 GPa.
• DFT calculations suggest superconducting current flows through the Pt layers, highlighting the role of the layered structure.

Conclusions:

• LaPt5As is a novel superconductor with a unique layered crystal structure, suggesting this structure is key to its superconductivity.
• High-pressure synthesis is effective for producing single-phase superconducting LaPt5As and offers potential for discovering new high-pressure phases.
• The layered structure of LaPt5As allows for conceivable structural modifications, opening avenues for future material design.