Multimodal analysis of surface properties and charge dynamics in teflon-FEP electrets - Ginja,^Gabriel^Augusto; Altafim, Ruy Alberto Pisani; Altafim, Ruy Alberto Corrêa; Carmo, João Paulo Pereira do; Queiroz, Alvaro Antonio Alencar de (IEEE Transactions on Dielectrics and Electrical Insulation, 2026)