LUMINESCENCE AND ENERGY MIGRATION IN A ONE-DIMENSIONAL GD3- CA4GDO(BO3)(3)( COMPOUND )

Energy transfer processes is nominally pure and Mn2+- and Dy3+-doped C a4GdO(BO3)(3) have been investigated. The host lattice is characterise d by linear Gd3+ chains. At 4.2 K long range energy migration is hampe red by Gd3+ traps. At room temperature the excitation energy is trappe d by the accepters (viz. Mn2+ and Dy3+) or by unknown defects and impu rities. The fraction of the latter is estimated to be 1 x 10(-5) and 8 x 10(-5) in undoped Ca4GdO(BO3)(3) fired in air or fired in a reducin g atmosphere, respectively. The energy migration in this compound appe ars to be strictly one-dimensional. The Gd3+ --> Gd3+ intrachain energ y transfer probability is estimated to be 2 x 10(11) s(-1). The interc hain Gd3+ --> Gd3+ energy transfer probability is smaller than the rad iative relaxation probability of Gd3+.