Judd-Ofelt analysis of Tm super(3+) in La sub(3)Ga sub(5.5)Ta sub(0.5)O sub(14) ceramic with granular structure

A Judd-Ofelt analysis was performed on a langatate (La sub(3)Ga sub(5.5)Ta sub(0.5)O sub(14)) translucent ceramic sample doped with 1 at% Tm super(3+). Due to the scattering of the transmitted light, the effective thickness of the sample is unknown and the absorption spectrum of Tm super(3+) in langatate ceramic sample is obtained in relative units. The absorption spectrum was calibrated using the magnetic-dipole contribution to the super(3)H sub(6) arrow right super(3)H sub(5) transition. The Judd-Ofelt parameters obtained are: Omega sub(2)=2.6510 super(-20) cm super(2), Omega sub(4)=0.8010 super(-20) cm super(2), Omega sub(6)=1.8610 super(-20) cm super(2). The electric-dipole and magnetic-dipole transition probabilities, radiative lifetimes and luminescence branching ratios were calculated. The calibration allowed the estimation of the 'effective' thickness of the ceramic sample which was approximately four times larger than the geometric thickness.