Cross-Correlation Measurement of the Turn-On Delay and Pulsewidth of a Q-Switched Two-Section Semiconductor Laser

Cross-correlation techniques were employed for direct optical measurement of a Q-switched two-section semiconductor laser output versus electrical bias. Since our switching scheme is not limited by external connections to the device, the ultrafast dynamics of the diode laser can be investigated. In particular, a turn-on delay as small as 70 ps was recorded with picosecond accuracy. In addition, the FWHM and peak power of the Q-switched pulse were also measured. A numerical simulation was performed, and good agreement with experimental results was achieved.