2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/119622In this paper nonlinear Klein-Gordon equation for heat and mass transport in nanoscale was proposed and solved. It was shown that for ultra-short laser pulses nonlinear Klein-Gordon equation is reduced to nonlinear d`Alembert equation. The implicit solution of the d`Alembert equation for ultrashort laser pulses was obtained Key words: nonlinear Klein-Gordon equation, d`Alembert equation, nanoscale transport5 pagesGeneral Physicstext