Solvated electrons in polar liquids as epsilon-near-zero materials tunable in the terahertz frequency range
Chemical Physics
2025-05-29 v1 Materials Science
Abstract
Electrons in polar liquids give rise to a polaron resonance at a terahertz (THz) frequency \nu_0 depending on electron concentration. The impact of this resonance on light propagation is studied in experiments, where a femtosecond pump pulse generates electrons via multiphoton ionization and a THz probe pulse propagated through the excited sample is detected in a phase-resolved way. We observe a behavior characteristic for epsilon-near-zero (ENZ) materials with strongly modified phase and group velocities around \nu_0, and a broadening of the THz pulse envelope below \nu_0. Calculations based on a local-field approach reproduce the ENZ behavior.
Keywords
Cite
@article{arxiv.2505.22198,
title = {Solvated electrons in polar liquids as epsilon-near-zero materials tunable in the terahertz frequency range},
author = {Matthias Runge and Michael Woerner and Denys I. Bondar and Thomas Elsaesser},
journal= {arXiv preprint arXiv:2505.22198},
year = {2025}
}