Abstract: An optical modulator includes at least one waveguide medium that receives light. An absorption medium absorbs the light under predefined conditions and outputs optically modulated light. The absorption medium is comprised of a Ge-based structure. The Ge-based structure uses the Franz-Keldysh effect to create said optically modulated light.

Abstract: A photodetector device includes a plurality of Ge epilayers that are grown on a substrate and annealed in a defined temperature range. The Ge epilayers form a tensile strained Ge layer that allows the photodetector device to operate efficiently in the C-band and L-band.

Abstract: A photodetector device includes a plurality of Ge epilayers that are grown on a substrate and annealed in a defined temperature range. The Ge epilayers form a tensile strained Ge layer that allows the photodetector device to operate efficiently in the C-band and L-band.

Abstract: An optical planar waveguide comprising erbium-doped silica glass has an active core with a length of not less than 5 cm, typically in a range of 0.2 cm to 100 meters, preferably 0.5 cm to 5 meters. Preferably, the active core of the planar waveguide has a serpentine shape. The radius of curvature of the serpentine planar waveguide is in a range of about 0.1 mm to 50 mm, preferably about 20 mm. The erbium-doped silica glass has a low concentration of erbium atoms, corresponding to an Er/Si atomic ratio in a range of 10−5 to 2×10−3, preferably in a range of about from 5×10−5 to 3×10−4. A layer of erbium-doped silica glass having a low concentration of erbium is formed on a substrate by sublimating a solid source of an erbium-containing metal organic precursor compound, mixing vaporized molecules of the precursor with other gases for forming silica glass, and: generating a plasma in the reaction mixture.

Abstract: A photodetector device includes a plurality of Ge epilayers that are grown on a substrate and annealed in a defined temperature range. The Ge epilayers form a tensile strained Ge layer that allows the photodetector device to operate efficiently in the C-band and L-band.

Abstract: An optical modulator includes at least one waveguide medium that receives light. An absorption medium absorbs the light under predefined conditions and outputs optically modulated light. The absorption medium is comprised of a Ge-based structure. The Ge-based structure uses the Franz-Keldysh effect to create said optically modulated light.