Highly selective 1.55 /spl mu/m InP/air gap micromachined Fabry-Perot filter for optical communications

The authors report a highly selective and tunable optical filter at 1.55 µm using a Fabry-Perot resonator with micromachined InP-air gap distributed Bragg reflectors. The resonance full width half maximum, as measured by micro-reflectivity experiments, is close to 0.4 nm (around 1.55 µm) and is compatible with wavelength division multiplexing specifications for optical telecommunications.