electro-optic modulator whose 147 GHz bandwidth at 49 K exceeds the room temperature bandwidth of 126 GHz The bandwidth of the modulator is limited only by high contact resistance and its intrinsic RC

The present study reports on an electro-optic modulator with an impressive bandwidth of 14.7 GHz at a low temperature of 4.9 K. This bandwidth surpasses the room temperature bandwidth of 12.6 GHz. The limiting factor for the modulator's bandwidth is the high contact resistance, as its intrinsic RC-limited bandwidth is measured to be 200 GHz at 4.9 K. These results demonstrate the potential for developing high-bandwidth modulators at low temperatures.