Erbium-doped silicon laser

Abstract

Erbium-doped silicon is studied as an active lasing medium. Capture and emission properties of recombination centers introduced by erbium atoms in the silicon lattice is analyzed. Electron-hole recombination at these sites are equated to find out the excitation and de-excitation rates of erbium. A two level system is considered to analyze the effects of stimulated emission and confinement of the 1.54 μm erbium light in the optical cavity. For a cavity length of 300 μm with mirror reflectivities of 90%, and an optimistic absorption coefficient of 5 cm−1, a population inversion of 1.4x1018 cm−3 is estimated as the threshold value. On the assumption of 1019 cm−3 of optically active erbium sites with an overall spectral linewidth of 1A, linear increase of optical power has been estimated for laser drive currents of the order of A/cm2. Theoretical calculation shows direct modulation capabilities of the proposed silicon laser. Modulating frequencies up to GHz. level with power levels of wattage range is estimated.Erbium-doped silicon is studied as an active lasing medium. Capture and emission properties of recombination centers introduced by erbium atoms in the silicon lattice is analyzed. Electron-hole recombination at these sites are equated to find out the excitation and de-excitation rates of erbium. A two level system is considered to analyze the effects of stimulated emission and confinement of the 1.54 μm erbium light in the optical cavity. For a cavity length of 300 μm with mirror reflectivities of 90%, and an optimistic absorption coefficient of 5 cm−1, a population inversion of 1.4x1018 cm−3 is estimated as the threshold value. On the assumption of 1019 cm−3 of optically active erbium sites with an overall spectral linewidth of 1A, linear increase of optical power has been estimated for laser drive currents of the order of A/cm2. Theoretical calculation shows direct modulation capabilities of the proposed silicon laser. Modulating frequencies up to GHz. level with power levels of wattage range is estimated.