Terahertz emission properties from palladium/silicon interface

Laser terahertz (THz) emission and detection system for investigating the catalytic metal/semiconductor interface of the hydrogen sensors was proposed and developed. THz radiation from palladium/silicon structures was successfully obtained. The properties of THz radiation under hydrogen and nitrogen gas mixture were investigated. The peak amplitude of THz radiation was decreased by increasing the volume concentration of hydrogen gas. This change in the amplitude can be explained by change in the local field near the surface of silicon. This result indicates that the system a potential tool for nondestructive and noncontact measurement of the hydrogen sensors.