Optical Frequency Comb Generation from Semiconductor Lasers using Optical Injection and Pulsed Gain Switching

An Optical Frequency Comb (OFC) Generator is a laser source emitting a coherent radiation with an equally spaced group of optical frequencies. OFCs have been used in numerous fields, such as optical communications [1], RF photonics [2] and infrared spectroscopy [3]. Relatively low repetition rate OFCs (100–1000 MHz) are especially suited for dual comb spectroscopic applications. Low repetition rate OFCs from Gain-Switched (GS) semiconductor lasers using sinusoidal excitation have been reported for spectroscopic applications [4]. On the other hand, the generation of ultra-short optical pulses by pulsed excitation GS has been demonstrated [5], but as far as we know, it has not been used for OFC generation.