Crystal characterization and optical spectroscopy of Eu3+-doped CaGdAlO4 single crystal fabricated by the floating zone method

A highly transparent Eu3+-doped CaGdAlO4 (CGA) single crystal is grown by the floating zone method. The segregation coefficient, x ray diffraction, and x ray rocking curve are detected, and the results reveal that the single crystal is of high quality. The f-f transitions of Eu3+ in the host lattice are discussed. The D-5(0)-F-7(2) emission transition at 621 nm (red light) is dominant over the D-6(0)-F-7(1) emission transitions at 591 and 599 nm (orange light), agreeing well with the random crystal environment of Eu3+ ions in a CGA crystal. The decay time of Eu:D-5(0) is measured to be 1.02 ms. All the results show that the Eu:CGA crystal has good optical characterization and promises to be an excellent red- fluorescence material.