Simultaneous light emissions from erbium-thulium silicates and oxides on silicon in the second and third telecommunications bands

We demonstrate simultaneous light emissions in O (1260-1360 nm), S (1460-1530 nm), and C (1530-1565 nm) telecommunications bands from films composed of mixtures of polycrystalline Er2xTm2-2xSiO5 and Er2xTm2-2xSi2O7 and of polycrystalline Er2xTm2-2xO3 grown by radio frequency (rf) magnetron sputtering using polycrystalline Tm2O3, Er2O3 and SiO2 targets on Si(100) substrates. Photons are emitted in the O and S + C bands when the samples are optically excited at 532 nm and in the S and C bands when excited at 785 nm. The simultaneous dual-wavelength light emissions are discussed in terms of energy transfers between Er3+ and Tm3+ ions in the polycrystalline Er-Tm compounds.