LONG RESONATOR MICROMACHINED TUNABLE GAAS-ALAS FABRY-PEROT FILTER

We present novel concepts for tunable optical filters, Long resonant c avities of about 30-mu m length have been realized with two-chip desig ns. GaAs technology has been applied to filters that are designed for the use in dense wavelength-division multiplexing (WDM) at wavelengths around 1550 nm. A finesse of 46.7, a full-width at half-maximum (FWHM ) of 1.2 nm and electrostatic tuning over a range of 103 nm with an ap plied voltage of 35 V has been achieved. An alternative tuning concept that allows to tune the resonator length 4 mu m by heating Ni-Cr resi stors placed on the suspending beams of a membrane with an applied vol tage of 2.7 V has been realized.