Title :
A traveling-wave-type LiNbO3 optical modulator with superconducting electrodes
Author :
Yoshida, Keiji ; Kanda, Yutaka ; Kohjiro, Satoshi
Author_Institution :
Dept. of Electron. Device Eng., Kyushu Univ., Fukuoka, Japan
fDate :
7/1/1999 12:00:00 AM
Abstract :
The design and performance of a LiNbO3 optical modulator employing low-loss superconducting electrodes as a transmission line for a traveling-wave signal have been studied. In the case of velocity matching between signal and optical waves using a shielding plane on top of a coplanar waveguide electrode, numerical calculations of the attenuation constants of superconducting transmission lines indicate that the performance of the optical modulator can be much superior to that using normal metals, with respect to the figure-of-merit of bandwidth/driving voltage in the case of extended coupling lengths. Microwave operation of a velocity-matched traveling-wave-type optical modulator with superconductor electrodes has been confirmed at low temperatures down to 4.2 K in the frequency range between DC and 26.5 GHz
Keywords :
coplanar waveguide components; electro-optical modulation; electrodes; lithium compounds; microwave photonics; optical communication equipment; superconducting microwave devices; superconducting transmission lines; 0 to 26.5 GHz; 4.2 K; CPW electrode; LiNbO3; LiNbO3 optical modulator; attenuation constants; bandwidth; coplanar waveguide electrode; driving voltage; low-loss electrodes; microwave operation; shielding plane; superconducting electrodes; superconducting transmission line; traveling-wave signal; traveling-wave-type modulator; velocity matching; Coplanar transmission lines; Coplanar waveguides; Electrodes; Optical attenuators; Optical design; Optical modulation; Optical waveguides; Signal design; Superconducting microwave devices; Superconducting transmission lines;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
