Broadband and low driving-voltage LiNbO/sub 3/ optical modulator with high T/sub c/ superconducting transmission line

A new design theory is presented of the high-T/sub c/ superconducting broadband booster circuit for a LiNbO/sub 3/ optical modulator. Based on this theory we studied the gain and bandwidth characteristics of the modulator using a transmission line model. We also designed the practical booster circuit using an electromagnetic wave simulator and demonstrated the optical modulator with broadband and high voltage gain as expected from the theory.