Low threshold simultaneous multi-wavelength amplified spontaneous emission modulated by the lithium fluoride/Ag layers.

This paper describes a multi-wavelength amplified spontaneous emission (ASE) with multilayer stacked active planar waveguides. A modulating layer of Ag is applied to make a good confinement of ASE in one active layer, while a lithium fluoride layer is inserted between the active layer and the modulating layer to avoid fluorescence quenching and confine the pump energy in one waveguide. Under optical pumping, ASE at 503 and 662 nm corresponding to the respective active layer are simultaneously observed, with extremely low thresholds at ~37.2 and ~39.7 KW/cm2.