Authors: K Linganna M Rathaiah V Venkatramu C K Jayasankar
Publish Date: 2013/08/20
Volume: 115, Issue: 2, Pages: 689-696
Abstract
Trivalent holmiumdoped K–Sr–Al phosphate glasses mathrmP 2mathrmO 5–mathrmK 2mathrmO–SrO–mathrmAl 2mathrmO 3–mathrmHo 2mathrmO 3 were prepared and their spectroscopic properties have been evaluated using absorption emission and excitation measurements The Judd–Ofelt theory has been used to derive spectral intensities of various absorption bands from measured absorption spectrum of 10 mol mathrmHo 2mathrmO 3doped K–Sr–Al phosphate glass The Judd–Ofelt intensity parameters varOmega lambda times1020~mathrmcm2 have been determined of the order of varOmega 2 = 1139 varOmega 4 = 359 and varOmega 6 = 292 which in turn used to derive radiative properties such as radiative transition probability radiative lifetime branching ratios etc for excited states of mathrmHo3+ ions The radiative lifetimes for the 5F 4 5S 2 and 5F 5 levels of mathrmHo3+ ions are found to be 169 296 and 317 μs respectively The stimulated emission crosssection for 205μm emission was calculated by the McCumber theory and found to be 93times102 1~mathrmcm2 The wavelengthdependent gain coefficient with population inversion rate has been evaluated The results obtained in the titled glasses are discussed systematically and compared with other mathrmHo3+doped systems to assess the possibility for visible and infrared device applicationsOne of the authors Dr V Venkatramu is grateful to Council of Scientific and Industrial Research CSIR New Delhi for the sanction of major research project No 031229/12/EMRII dated 16 April 2012 This work has also been supported by Mega project No 2009/34/36/BRNS/3174 dt 12022010 sanctioned to Prof CK Jayasankar through MoU between Sri Venkateswara University Tirupati and Bhabha Atomic Research Centre Mumbai
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