Abstract

Millimeter waves have been generated by driving HBTs with both mode locked and cw semiconductor lasers. The mode locked diode lasers incorporated a saturable absorber section and produced <2.5 ps pulses at 65.12 GHz. Millimeter waves generated in the high frequency HBTs were radiated into free space by using integrated printed circuit device/antenna circuits. In subsequent experiments, cw optical mixing techniques were also used to generate millimeter waves. Here, single frequency, stabilized semiconductor lasers operating at both 850 nm and 1.3 μm were mixed in the active regions of the HBTs. These long wavelength lasers were chosen because they are optimally absorbed in the active regions of the devices and therefore provided the highest optical-to-millimeter-wave conversion efficiencies. In order to optimize the performance and configuration of these new millimeter wave sources, we also incorporated them on wafer optical feeds by using polyimide guides deposited with a direct laser writing technique. This approach permits a high degree of fan-out and the use of multiple radiating elements. These experiments demonstrate a new architecture to form compact, all-solid-state sources of millimeter waves that use wafer scale optical interconnections to form novel coherent arrays.

© 1992 Optical Society of America