Electron-hole liquid in biological tissues under ultrahigh-dose-rate ionizing radiation
Phys. Rev. Applied 25, 064023 – Published 4 June, 2026
DOI: https://doi.org/10.1103/3ly7-yswy
Abstract
We develop a quantitative model of ionization processes in biological tissues under ultrahigh-dose-rate (UHDR) radiation. The underlying conjecture is that of electron-hole liquid (EHL) formation in water-based substances of biological tissues. Unlike the earlier known EHL in semiconductor crystals, the charge carriers here are poorly mobile, owing to strong interactions with the background (solvated electrons, etc.); hence, EHL resembling ionic melts is formed. Similar to all ionic systems, Coulomb coupling makes that EHL energetically favorable that leads to recombination barriers, suppressing subsequent structural transformations. In particular, the generation of secondary reactive species in such an EHL becomes limited, translating into a reduction of biological damage and tissue-sparing effects. We show how these processes are sensitive to the tissue quality and frequency dispersion of the dielectric permittivity. Equations for dose and dose rate defining the sparing thresholds are derived.
