Optoelectronic mixing using a novel dual-mode locking semiconductor laser at 40 GHz

In this work we present a new mode-locked device that can be used for photonic millimetre-wave applications, and more specifically optoelectronic mixing. This device is based on a mode-locked MQW-DFB multisection laser that presents for certain bias conditions a dual longitudinal mode behavior (39.5 GHz separation) that can be used for mm-wave generation and transmission. In this work we focus on the possibility of achieving optoelectronic mixing using this new device through the injection of an intermediate frequency (IF) signal in one of the sections (absorber) while the gain section is used to mode-locked the two longitudinal modes by injecting a signal at 39.5 GHz. Demonstration of the optical up-conversion is carried out through the study of the modulation sidebands for different IF frequencies and a spurious free dynamic range (SFDR) of 65dB-HZ2/3 has been measured. Transmission of an up-converted NRZ 32Mbps PRBS signal using this device for optical mixing is also demonstrated.