Er–Tm co-doped materials for on-chip ultra-broadband waveguide amplifier

On-chip ultra-wideband optical waveguide amplifiers are crucial for short-distance optical interconnections that utilize wavelength division multiplexing (WDM) technology. Silicon optical amplifiers still face significant challenges due to the indirect-band-gap nature and low rare earth solubility of silicon. This paper prepared a series of Er3+-Tm3+ co-doped La2O3–Al2O3 glasses that are expected to be used in on-chip ultra-broadband optical waveguide amplifiers by aerodynamic levitation (ADL) technique, and further studied their luminescence characteristics and energy transfer process. Research results indicate that the glass composition 5Er2O3-0.6Tm2O3-43.4La2O3–51Al2O3 is an optimal optical waveguide amplifier host material due to its excellent luminescence properties and ultra-broadband flat photoluminescence spectrum extending up to 440 nm. Moreover, positive gain can be obtained with a population ratio greater than 0.2, which further illustrates its feasibility as a matrix material for ultra-broadband optical waveguide amplifiers. The advancement of this material is expected to significantly aid in the fabrication and progress of next-generation ultra-wideband optical waveguide amplifiers.