Lifetime Widths of Surface States on Magnetic Lanthanide Metals

TL;DR

This study uses low-temperature scanning tunneling spectroscopy to analyze surface state electronic structures and dynamics on lanthanide metals, revealing how magnetic exchange and scattering mechanisms vary with 4f electron occupancy.

Contribution

It provides new insights into the scaling of magnetic exchange splitting and the dominant scattering processes affecting surface state lifetimes across lanthanide metals.

Findings

Magnetic exchange splitting scales with 4f spin and an effective exchange constant.

Surface state lifetimes are dominated by electron-phonon scattering in occupied states.

Electron-magnon scattering dominates the unoccupied surface state dynamics.

Abstract

Low-temperature scanning tunneling spectroscopy is used to study electronic structure and dynamics of d-like surface states of trivalent lanthanide metals from La to Lu. The magnetic exchange splitting of these states is found to scale with the 4f spin multiplied by an effective exchange-coupling constant that increases with 4f occupancy in an approximately linear way. The dynamics of the surfaces states, as revealed by the lifetime width, is dominated by electron-phonon scattering in the occupied region and by electron-magnon scattering in the unoccupied region, respectively.