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Cation vacancies on both sublattices (, ) have been identified in homoepitaxial pulsed laser deposited films using high intensity variable energy positron annihilation lifetime spectroscopy (PALS) measurements. Film nonstoichiometry was varied by varying laser fluence. PALS showed that on increasing the fluence above the value, the concentration ratio systematically increased. Reducing the fluence into the Ti-poor region below resulted in additional vacancy cluster defect formation. Vacancy concentrations greater than were observed in all films.