Photon-induced electron-detachment from negatively charged glass and ceramic substrates.

Understanding how dielectric materials accumulate and release charge during plasma exposure is vital for modeling plasma–surface interactions. While charge buildup due to ion and electron bombardment has been extensively investigated, the mechanisms of charge removal by low-energy photon exposure are not understood. This study explores the photon-induced electron-detachment (PIED) of electrons from dielectric surfaces previously charged by exposure to ionized nitrogen gas at atmospheric pressure. Preliminary measurements show that the electron-detachment response is influenced by the initial surface charge density, with discharge dynamics that exhibit nonlinear decay behavior. Experimental results obtained for glass and ceramic substrates demonstrate that the electron-detachment yield does not follow trends predicted by electron affinity values alone. These observations suggest that surface states and charge trapping mechanisms significantly affect electron detachment under gas-ionizing charging conditions. The ability to modulate surface charge using low-energy photons offers a promising pathway for non-destructive control of charge accumulation in applications such as plasma diagnostics, surface modification, microelectronics, and spacecraft charging mitigation.