The 7 × 1 Fermi Surface Reconstruction in a Two-dimensional f -electron Charge Density Wave System: PrTe3

Area of Science:

• Condensed Matter Physics
• Materials Science
• Solid State Chemistry

Background:

• Charge density waves (CDWs) are prevalent phenomena in low-dimensional materials.
• Understanding the interplay between electronic structure and CDW formation is crucial for materials design.

Purpose of the Study:

• Investigate the electronic structure of the CDW system PrTe3.
• Elucidate the role of Pr 4f and Te 5p hybridization in CDW instability.
• Characterize the modulated structure in the CDW phase.

Main Methods:

• Angle-resolved photoemission spectroscopy (ARPES)
• X-ray absorption spectroscopy (XAS)
• Pr 4f resonant photoemission spectroscopy (RPES)
• First-principles band structure calculations

Main Results:

• Pr ions are nearly trivalent, with partial filling supporting CDW instability.
• Pr 4f states hybridize with Te 5p states, contributing significantly to CDW formation.
• Observed Fermi surface features align with a 7×1 CDW supercell, including shadow bands from band folding and CDW reconstruction.
• Nearly 2D electronic character and in-plane orbital nature of Te 5p states near the Fermi level are confirmed.

Conclusions:

• The electronic structure of PrTe3 is strongly influenced by Pr 4f-Te 5p hybridization, driving the CDW instability.
• The observed modulated structure and Fermi surface properties are consistent with theoretical predictions for a 7×1 CDW.
• PrTe3 exhibits characteristics of a nearly two-dimensional material near the Fermi level.