Spectroscopic analysis and efficient diode-pumped 2.0μm emission in Ho(3+)/Tm(3+) codoped fluoride glass

Intense 2.0μm emission has been obtained in Ho(3+)/Tm(3+) codoped ZBLAY glass pumped by common laser diode. Three intensity parameters and radiative properties have been determined from the absorption spectrum based on the Judd-Ofelt theory. The 2μm emission characteristics and the energy transfer mechanism upon excitation of a conventional 800nm laser diode are investigated. Efficient Tm(3+) to Ho(3+) energy transfer processes have been observed in present glass and investigated using steady-state and time-resolved optical spectroscopy measurement. The energy transfer microscopic parameter has been calculated with the Inokuti-Hirayama and Förster-Dexter models. High quantum efficiency of 2μm emission (80.35%) and large energy transfer coefficient from Tm(3+) to Ho(3+) indicates this Ho(3+)/Tm(3+) codoped ZBLAY glass is a promising material for 2.0μm laser.