Experimental and density functional theory study of thermionic emission and narrow total-energy distribution from an yttrium oxide electron emitter
Phys. Rev. Applied 25, 044031 – Published 13 April, 2026
DOI: https://doi.org/10.1103/pkhq-5stm
Abstract
We measure the total-energy distribution of thermally emitted electrons from tungsten, lanthanum hexaboride, and yttrium oxide. The latter exhibits a surprisingly narrow distribution, with a full width at half maximum of approximately across a broad temperature range. We detail our simulation-experiment approach to account for the response of the energy analyzer and energy-broadening mechanisms, establishing the validity of the acquired spectra. We also present electronic-structure calculations using density functional theory that reveal narrow, localized states arising from oxygen vacancies and yttrium self-interstitials, which may be responsible for the observed electron energy distributions. This work helps strengthen the link between thermal electron emission and the properties of the electron-emitting material.
