PbTe(111) Sub-Thermionic Photocathode: A Route to High-Quality Electron Pulses

Abstract

The emission properties of PbTe(111) single crystal have been extensively investigated to demonstrate that PbTe(111) is a promising low root mean square transverse momentum (Δp${}_T$) and high brightness photocathode. The density functional theory (DFT) based photoemission analysis successfully elucidates that the 'hole-like' Λ${}_6^{+}$ energy band in the $L$ valley with low effective mass $m^{\ast }$ results in low Δp${}_T$. Especially, as a 300K solid planar photocathode, Te-terminated PbTe(111) single crystal is expected to be a potential 50K electron source.

DFT Calculations, PbTe(111), Photoemission, Photocathodes, Statistical Modeling, Band Structure, Fermi Surface