Fermi surface of LaFe₂P₂-a detailed density functional study

Area of Science:

• Condensed Matter Physics
• Materials Science
• Computational Physics

Background:

• Angular-dependent de Haas-van Alphen (dHvA) measurements provide detailed Fermi surface mapping.
• Density functional theory (DFT) calculations offer high-precision electronic structure but are sensitive to input parameters.

Purpose of the Study:

• Investigate the sensitivity of the electronic band structure and Fermi surface topology of LaFe2P2 to structural parameters and computational approximations.
• Compare theoretical calculations with experimental dHvA data.

Main Methods:

• Performed detailed DFT electronic structure calculations for LaFe2P2.
• Systematically varied the P atom position (z parameter) and the treatment of La 4f states.
• Compared calculated Fermi surface properties with experimental dHvA measurements.

Main Results:

• Calculated band structure and Fermi surface topology of LaFe2P2 exhibit high sensitivity to the P atom's z parameter.
• The treatment of La 4f states significantly impacts the calculated electronic structure and Fermi surface.
• Small variations in these parameters lead to distinctive changes in calculated band structure and topology.

Conclusions:

• Accurate experimental determination of the pnictide z parameter at low temperatures is essential for precise electronic structure calculations.
• Sophisticated treatment of La 4f states is crucial for reliable calculations in LaFe2P2 and related La-containing compounds.
• Findings highlight the importance of structural and electronic configuration details for accurate theoretical predictions in 122 materials.