Innovation in Specialty Glass
NP Photonics' technology foundation is proprietary specialty phosphate, germanate, and tellurite glasses—the key enabler for our fiber-based lasers, amplifiers and ASE sources.
At the heart of fiber lasers and amplifiers is the active fiber—most commonly based on silica host glass. However, the ability to dope silica glass fibers with the necessary high concentrations of rare earth ions—such as erbium, ytterbium, thulium, and holmium—is limited due to clustering and nonlinear up-conversion - effects that degrade gain fiber efficiency. As an alternative, NP Photonics has developed highly doped phosphate glass fibers. The dopant concentrations in this glass can be 100 times greater than in silica without any negative effect to the optical gain. As a result, highly doped phosphate glass fibers can produce large gain per unit length (typically 5 dB/cm). This enables a variety of optical devices that make use of high optical gain in a short length—most notably high-power single-frequency fiber lasers and short-length (low-latency) fiber amplifiers.
Enabling Laser Technologies
Our specialty optical fibers are used in unique, high-performance fiber laser products; field-tested in applications on Earth and in space.
NP Photonics' unique phosphate fibers are incorporated into very narrow linewidth (< 500 Hz) fiber lasers. A short length (< 2 cm) optical fiber cavity enables the compact packaging behind our environmentally robust laser platform. The low frequency and phase noise performance is superior to solid state lasers, and is highly attractive for interferometric fiber optic sensing applications. Moreover, our fiber lasers have passed rigorous space-qualification tests with NASA, and an NP Photonics fiber laser has even been used in space on a mission to the International Space Station.
A wide range of applications becomes possible with our phosphate and germanate fibers due to their high-gain-per-unit length—most notably the distortion-free amplification of short (nanosecond, picosecond, and femtosecond) pulses. Active phosphate fibers are used in LIDAR amplifiers capable of power- and energy-scaling, transform-limited, single-frequency pulses for atmospheric sensing of oxygen, carbon dioxide, and trace gases.
Capabilities in the Mid-IR
Optical fibers created with NP Photonics' proprietary materials are opening up new parts of the optical spectrum for fiber-based devices.
We have developed highly transmitting tellurite glass, fibers, and fiber cables to cover mid-infrared (mid-IR) wavelengths (2 micron to 5 micron). In this range, standard silica fibers are totally opaque, and other alternatives, such as fluorides and chalcogenides, suffer from various deficiencies. We have undertaken a fundamental study of the tellurium oxide glass system, selected glass compositions that have low absorption in the mid-IR band, and successfully produced glass and fiber with substantially no hydroxyl OH—a significant source of unwanted absorption. These low loss (< 0.2 dB/m) and robust optical fibers are capable of transporting, multiplexing, and distributing high-power mid-IR laser light from optical parametric amplifiers, quantum cascade lasers, and supercontinuum fiber lasers.
Partnership & Inventions
Through commercial and government partnerships, NP Photonics continues to develop high-value-added glass and fiber materials—and we continue to pursue our goal of offering highly differentiated, high-performance fiber-based devices for scientific, industrial, and defense applications.