In this work, we investigate a new type of fluoride glasses modified by AlðPO 3 Þ 3 with various Tm 3þ ∕Ho 3þ doping concentrations. The introduced PO − 3 plays an effective role in improving the glass-forming ability and thermal stability. Besides, 1.47, 1.8, and 2.0 μm emissions originating from Tm 3þ and Ho 3þ , respectively, are observed. The spectroscopic properties and energy transfer mechanisms between Tm 3þ and Ho 3þ are analyzed as well. It is noted that the higher predicted spontaneous transition probability (118.74 s −1 ) along with the larger product of measured decay lifetime and the emission cross section (σ emi × τ) give evidence of intense 2.0 μm fluorescence.