Spin-Polarized Photoelectrons in the Vicinity of Spectral Features

TL;DR

This paper explores how Fano resonances can produce high spin polarization in photoelectrons from rare gases, especially near spectral features, and provides a framework for achieving spin polarization across ionization regimes.

Contribution

It introduces a general framework for achieving spin polarization in photoionization, emphasizing the role of Fano resonances and spectral features.

Findings

Fano resonances yield higher spin polarization ($ extgreater40\\%$) in rare gases.

Spin polarization reaches 100 extpercent when measured in coincidence with photoion.

Spin polarization increases in angle-resolved spectra near spectral features.

Abstract

It has been shown by Fano (1969) https://doi.org/10.1103/PhysRev.178.131 that photoionization of a c{\ae}sium atom by a laser pulse tuned to the vicinity of a Cooper minimum generates spin-polarized electrons. Here we show that while photoionization of rare gases does not provide large spin polarization in the vicinity of the Cooper minimum, the Fano resonances yield much higher overall spin polarization ($\ge40\%$). The spin polarization increases in angle-resolved photoelectron spectra, and reaches $100\%$ when measured in coincidence with the photoion. We provide a general framework for achieving spin polarization in photoionization irrespective of the ionization regime.