The performance of pigtailed annealed proton exchange LiNbO3 modulators at cryogenic temperatures

Integrated optic modulators have been proposed for transmitting signals from electronic and electrooptic devices which must operate at 77 K and colder. In this letter, the V/spl pi/ of LiNbO/sub 3/ modulators at temperatures as cold as 10 K are measured. A /spl sim/9.25% increase over room temperature values is seen. This increase is attributed primarily to a temperature dependence in r/sub 33/. In addition, temperature-induced insertion loss changes are evaluated for two different pigtailing techniques and one is shown to be suitable for cryogenic operation.