Grant: Discovery Grants Program - Individual

Q-switched fiber lasers have widespread applications such as range finding, laser sensing, LIDARs, nonlinear frequency conversion, free-space communications, and medical surgery. Among various Q-switching methods, passive Q-switching by use of saturable absorber (SA) offers a simple, convenient and efficient way to achieve high energy pulse. Transition metal doped crystals and semiconductor SA mirrors are currently available state-of-the-art SAs. However, the fabrication systems of growing crystals or semiconductor SAs are complex and costly. Furthermore, both approaches require using bulk optic components, which increases insertion loss and the complexity of the laser system. Therefore, investigating compact cost-effective Q-switched fiber lasers is very important. The goal of my research is to develop novel high performance cost-effective nanomaterial Q-switched fiber lasers. Recent advancements in nanomaterials are now enabling new research on pulsed fiber lasers. Single-walled carbon nanotubes (CNTs) and graphenes have emerged as innovative nanomaterials and have found practical photonic applications. They are excellent SAs and potential replacements for semiconductor-based SAs. This work builds on my ongoing research. In the proposed program, a number of challenging issues will be addressed, including the design and fabrication of low-insertion-loss nanomaterial based SAs, all-fiber passive components, laser pulse width control, single frequency operation, high pulse energy, dual-wavelength operations, synchronization of the dual-wavelength pulse, and its application in THz generation. The research and development will take the approaches of both experimental studies and comprehensive theoretical analyses. To obtain the desired optical performance, modeling, simulation, and design optimization will be performed. The combination of fiber lasers and nanomaterials presents new opportunities for developing innovative devices/technologies that have not been explored before and will lead to innovations in optics/photonics.