SBIR-STTR Award

Ultrafast infrared laser systems have been proposed for use in many areas of DOE and industrial applications. Current available infrared femtosecond lasers are unstable, complicated, cost-intensive, inefficient, and bulky. Fiber lasers have become key workhorses for power scaling of ultrafast laser sources because of their advantages including inherent simplicity, compactness, low-cost, high efficiency, outstanding heat-dissipating capability, and excellent beam quality. Leveraging on our substantial experience in developing ultrafast fiber lasers at 2 ?m and our unique short-length highly doped fiber laser technology for ultrashort pulse amplification with low nonlinear distortions, NP Photonics, in collaboration with the College of Optical Sciences at the University of Arizona, proposes to develop a compact and robust single-polarization ultrafast fiber laser source at 2.1 ?m with exceptional operation stability and reliability. In this Phase I program, we will focus on the development of a compact and robust mode-locked all-fiber laser oscillator with exceptionally high polarization extinction ratio and highly holmium-doped polarization maintaining fiber amplifiers for energy scaling of ultrafast laser at 2.1 ?m. A compact and robust ultrafast laser source at 2.1 ?m meeting or exceeding the requirements of DOE’s applications will be developed in Phase II. In addition to DOE applications, the proposed high- energy ultrafast lasers can also be used for direct energy weapons, material processing, highly nonlinear process in atoms and molecules, and scientific research.

Ultrafast infrared laser systems have been proposed for many DOE, DOD and industrial applications. Currently available infrared femtosecond lasers are unstable, complicated, expensive to purchase and maintain, inefficient, and bulky. Fiber lasers are becoming the preferred option for kW-class ultrafast laser sources because of their inherent simplicity, small size, low cost, high efficiency, outstanding heat-dissipating properties, and excellent beam quality. NP Photonics proposes to develop a compact and robust single-polarization-state ultrafast fiber laser source at 2.1 µm with exceptional operation stability and reliability based on our substantial experience in developing ultrafast fiber lasers at 2 µm and our unique short-length highly doped fiber laser technology. This project is a continuation of the successful Phase I work by NP Photonics where we have demonstrated the feasibility of the proposed compact and robust ultrafast laser source by successfully developing a stable linearly polarized mode-locked Ho-doped fiber laser oscillator at 2.1 µm with polarization extinction ratio > 25 dB, fabricating and testing Ho- doped fiber lasers pumped at 1950 nm, and demonstrating a 0.1 mJ all-fiber laser system at 2.1 µm. In Phase II, NP Photonics will focus on optimizing the mode-locked fiber laser oscillator, increasing the efficiency of Ho-doped fiber lasers, and developing a 5-mJ all-fiber ultrafast laser source at 2.1 µm. A compact and robust ultrafast laser prototype at 2.1 µm meeting or exceeding the requirements of the DOE’s applications will be developed and delivered to the DOE laboratory at the end of Phase II. Dual use applications for the proposed high energy ultrafast lasers include directed energy weapons, material processing, the study of highly nonlinear processes in atoms and molecules, imaging and threat detection, and scientific research.