Conformal pixellated MQW modulator structure for modulating retroreflector applications

We have developed a conformal optical modulator structure comprising pixellated InGaAs-InAlAs multiple-quantum-well (MQW) electroabsorption modulators embedded in a polymer membrane for operation in the 1550-nm optical region. The MQW modulators retain their electrical and optical characteristics after the polymer embedding process, with leakage currents of less than 50 nA and modulation contrast ratios of 2 : 1. The radio frequency response of these modulators was shown to be dependent on the pixel size, with a 3-dB modulation frequency of over 200 MHz for a 225×125 μm² pixel. The conformal MQW modulator structure developed here can be used in applications requiring placement on a curved surface, such as in cat´s eye modulating retroreflectors.