hotelectron

Hotelectron is not a standard term in mainstream physics. When it is used, it typically refers to an electron that carries energy significantly above the thermal equilibrium of its surrounding material or environment, usually as a result of non-equilibrium excitation such as optical pumping or high electric fields. In this sense, hotelectron is often synonymous with the broader concept of a hot electron or hot carrier, though the one-word form is uncommon in scholarly literature.

In solid-state contexts, hot electrons describe carriers with an elevated effective temperature, referred to as Te, shortly after excitation. Their energy distribution is non-thermal immediately after excitation and then relaxes toward a Fermi-Dirac distribution as they thermalize with the lattice through electron-electron and electron-phonon interactions. The initial relaxation occurs on ultrafast timescales, typically from femtoseconds to picoseconds, with material-dependent rates.

Measurement and implications: hot electrons are studied using time-resolved techniques such as time-resolved photoemission spectroscopy, pump-probe optical spectroscopy, and terahertz conductivity measurements. They influence device performance in photovoltaics, photodetection, plasmonics, and photocatalysis by affecting transient spectra, charge transfer across interfaces, and instantaneous photocurrents. In practice, researchers usually use the terms hot electron or hot carrier, reserving hotelectron for informal or nonstandard usage.

See also: hot electron, hot carrier, non-equilibrium electron, electron-phonon interaction.