Modulated semiconductor dfb laser array with a mems-based rf switch

Abstract

Many approaches to tunable lasers use an array of DFBs, where each element of the array has a different wavelength. In some operations one element of the array is activated at a time depending on the desired wavelength. For modulated applications, an RF voltage is applied to a specific element of the DFB array, generally using an RF switch. In standard configurations, the demands on the switch are relatively difficult, generally requiring low RF insertion loss and good high frequency performance to 10 GHz. The DFB arrays are generally common cathode or common anode, depending on the type of the substrate used to fabricate the devices. Described herein is an array with a common cathode or anode configuration using a MEMS based switch that shorts the selected laser to RF ground. With this topology, preferably the off-state capacitance should be low with the MEMS switch.