title: Mid-infrared emission characteristic and energy transfer of Ho3+-doped tellurite glass sensitized by Tm 3+.
abstract: We report on 2.0-microm emission characteristic and energy transfer of Ho3+-doped tellurite glass sensitized by Tm3+ upon excitation of a conventional 808 nm laser diode. The Judd-Ofelt strength parameters, spontaneous radiative transition probabilities and radiative lifetime of Ho3+ have been calculated from the absorption spectra by using the Judd-Ofelt theory. Significant enhancement of 2.0-microm emission of Ho3+ has been observed with increasing Tm3+ doping up to 0.7 mol%. The energy transfer coefficient of the forward Tm3+-->Ho3+ is approximately 17 times larger than that of the backward Tm3+<--Ho3+ energy transfer. Our result indicates that the maximum gain of 2.0-microm emission, assigned to the transition of (5)I7-->(5)I8 of Ho3+, might be achieved from the tellurite glass at the concentration of 0.5 mol% of Tm2O3 and 0.15 mol% of Ho2O3. The high gain coefficient and quantum efficiency (1.16) along with the large value of the product of the stimulated emission cross-section and the measured radiative lifetime (4.12 x 10(-27) m(2)s) of the Ho3+/Tm3+-codoped tellurite glasses might find potential applications in efficient 2.0-microm laser.
authors: Key Lab of Specially Function Materials of Ministry of Education, and Institute of Optical Communication Materials, South China University of Technology, Guangzhou 510641, P. R. China.
authors: G X
authors: GX
authors: Chen
authors: Q Y
authors: QY
authors: Zhang
authors: G F
authors: GF
authors: Yang
authors: Z H
authors: ZH
authors: Jiang
mesh_terms: D000465:Algorithms; D002412:Cations / Q000737:chemistry; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004735:Energy Transfer; D005453:Fluorescence; D006695:Holmium / Q000737:chemistry*; D007834:Lasers; D010087:Oxides / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013691:Tellurium / Q000737:chemistry*; D013932:Thulium / Q000737:chemistry*; D014414:Tungsten / Q000737:chemistry; D015034:Zinc Oxide / Q000737:chemistry
chemical_list: D002412:Cations; D010087:Oxides; C016774:tellurium dioxide; D013932:Thulium; C511604:tungsten oxide; C033160:thulium oxide; C026660:tellurous acid; D013691:Tellurium; D015034:Zinc Oxide; D014414:Tungsten; D006695:Holmium