title: ZnGa2O4:Cr3+: a new red long-lasting phosphor with high brightness.
abstract: ZnGa2O4:Cr3+ is shown to be a new bright red UV excited long-lasting phosphor potentially suitable for in vivo imaging due to its 650 nm-750 nm emission range. Photoluminescence and X-ray excited radioluminescence show the 2E → 4A2 emission lines of both ideal Cr3+ and Cr3+ distorted by a neighboring antisite defect while long-lasting phosphorescence (LLP) and thermally stimulated luminescence (TSL) almost exclusively occur via distorted Cr3+. The most intense LLP is obtained with a nominal Zn deficiency and is related to a TSL peak at 335K. A mechanism for LLP and TSL is proposed, whereby the antisite defect responsible for the distortion at Cr3+ acts as a deep trap.
authors.affiliation: Chimie Paristech, Laboratoire de Chimie Matière Condensée de Paris, UPMC, Collège de France, UMR - CNRS 7574, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France. aurelie-bessiere@chimie-paristech.fr
authors.forename: Aurélie
authors.initials: A
authors.lastname: Bessière
authors.forename: Sylvaine
authors.initials: S
authors.lastname: Jacquart
authors.forename: Kaustubh
authors.initials: K
authors.lastname: Priolkar
authors.forename: Aurélie
authors.initials: A
authors.lastname: Lecointre
authors.forename: Bruno
authors.initials: B
authors.lastname: Viana
authors.forename: Didier
authors.initials: D
authors.lastname: Gourier