Optical amplification and electroluminescence at 1.5 μm is reported in Er-doped Zn2Si0.5Ge0.5O4 (ZSG:Er) on silicon. ZSG:Er films were deposited by rf sputtering from a composite target in Ar/O2 mixtures. Channel waveguides were fabricated by plasma etching with Cl/Ar. The refractive index of ZSG:Er was found to be 1.75 at 1.54 μm. Signal enhancement greater than 13 dB and an internal gain of ∼2 dB have been achieved by optically pumping a 4.7 cm ZSG:Er amplifier. Electroluminescence at 1.5 μm was achieved using an ac device structure with a ZSG:Er central layer and upper and lower dielectric layers. © 2004 American Institute of Physics.