Abstract: The subject invention pertains to electro-optic devices and, in particular, to an integrated-optic modulator with a linearized transfer curve. In a specific embodiment, an integrated-optic modulator with a linearized transfer curve can be formed in an electro-optic substrate and comprises an input Y-junction, a section of two coupled waveguides, followed by two output waveguide bends. Light from a CW optical source can be launched into the input Y-junction and amplitude modulated by applying an external voltage to the electrodes positioned on the top surface of the substrate. The modulator can be driven in both the uniform and Db configuration. By properly adjusting the length of the sections in the coupler with respect to the coupling length, the linearity of the transfer curve is improved. The subject invention is further concerned with realizing modulators with suppressed nonlinear distortions for analog optical links, for example fiber-optic communication links and cable television systems.
Abstract: The subject invention pertains to electro-optic devices and, in particular, to an integrated-optic modulator with a linearized transfer curve. In a specific embodiment, an integrated-optic modulator with a linearized transfer curve can be formed in an electro-optic substrate and comprises an input Y-junction, a section of two coupled waveguides, followed by two output waveguide bends. Light from a CW optical source can be launched into the input Y-junction and amplitude modulated by applying an external voltage to the electrodes positioned on the top surface of the substrate. The modulator can be driven in both the uniform and .DELTA..beta. configuration. By properly adjusting the length of the sections in the coupler with respect to the coupling length, the linearity of the transfer curve is improved The subject invention is further concerned with realizing modulators with suppressed nonlinear distortions for analog optical links, for example fiber-optic communication links and cable television systems.
Abstract: The subject invention pertains to a method of apodizing interaction in spatially-coupled waveguides capable of implementing any desired interaction-strength profiles, for example, alternating functions. Wavelength filters with various types of spectral response can be synthesized. In a preferred embodiment, a Butterworth-type interaction profile is disclosed which provides a flat-top response with suppressed sidelobes. The method according to the subject invention is based on spatially offsetting a single-mode waveguide with respect to a two-mode waveguide in which the anti-symmetric mode is excited by using a Y-junction mode splitter. The method can easily be implemented in vertically-coupled structures fabricated with the use of conventional fabrication processes. Various embodiments of the method implemented. The subject invention further pertains to the device produced in accordance with the methods of the subject invention.