Antiperovskite Superconductor LaPd₃P with Noncentrosymmetric Cubic Structure

Area of Science:

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

Background:

• Antiperovskite structures are actively explored for novel material properties.
• Previous work synthesized A(Pd3)P compounds with tetragonal or orthorhombic structures.

Purpose of the Study:

• To discover and characterize new antiperovskite phosphides.
• To investigate the superconducting properties of the newly synthesized LaPd3P.
• To elucidate the factors influencing its superconductivity through theoretical calculations.

Main Methods:

• Synthesis of LaPd3P antiperovskite phosphide.
• X-ray diffraction for structural determination (cubic system, I4̅3m space group).
• Measurement of superconducting transition temperature (Tc) and upper critical field.
• First-principles electronic band structure calculations.
• Analysis of density of states (DOS) and Fermi energy (EF).

Main Results:

• Discovery of LaPd3P, a new cubic antiperovskite prototype.
• Observed superconductivity with a transition temperature (Tc) of 0.28 K.
• Experimental Sommerfeld constant (γ) of 6.06 mJ mol⁻¹ K⁻² f.u.⁻¹, significantly higher than theoretical calculations (2.24 mJ mol⁻¹ K⁻² f.u.⁻¹).
• Discrepancy attributed to La deficiency (hole doping) and a pseudogap at the Fermi energy.
• Observed Tc is lower than BCS theory predictions.

Conclusions:

• LaPd3P represents a new structural prototype in antiperovskite phosphides.
• The material exhibits unconventional superconductivity, potentially due to its noncentrosymmetric crystal structure.
• La deficiency significantly impacts electronic properties and superconductivity.
• Further investigation into noncentrosymmetric superconductors is warranted.