Electrically tunable semiconductor Fabry-Perot filter

A key component of Wavelength Division Multiplexed (WDM) networks is a tunable broadband wavelength demultiplexer, with good selectivity and high tuning speed. In this communication we report low waveguide loss InGaAsP Fabry-Perot filters, grown by Metal Organic Vapor Phase Epitaxy, with tuning ranges up to 3.07 nm (380 GHz). These filters have waveguides with bandgap wavelengths between 1.3 and 1.48 μm so that they are transparent at zero bias and at low tuning currents (<2 mA) for 1.55 μm light. Their performance is independent of light level and they should be capable of high speed operation.