High-Performance, High-Isolation Optical Guided-Wave Device Arrays

Dense arrays of high-frequency photonic devices could provide many advantages to several Department of Defense systems currently under development. One example is their usage in phased-array radar systems. However, crosstalk from one device to the next must be kept at very low levels in order to not degrade the system performance. Often, crosstalk levels are required to be less than -100 dB electrical. These are very low levels when operation frequencies can be between I and 30 GHz. We propose to investigate methods of achieving dense arrays of traveling-wave electrooptic modulators that will satisfy these stringent crosstalk specifications. These methods will utilize various optical and electrical shielding structures integratable on the array substrate as well as on the electrical interconnect circuits required to impress the electrical drive signals onto the device array. In summary, the problem considered in this Proposal is that of dense arrays of highly-isolated, high-frequency photonic devices. The intent is to develop methods of optically and electrically isolating dense arrays of devices without compromising the high performance required of the individual devices. The techniques discussed here could have significant impact on systems applications in the defense and commercial sectors. Anticipated Benefits: The anticipated benefits of this R&D is the ability to integrate high-performance devices into cost-effective dense device arrays. These arrays can be used in systems where in the past the cost of the number of discrete devices required was prohibitive; thus capit- alizing on the large investments already made in the development of discrete high-performance devices.