Characterization of RPE APPLN Waveguides for Parametric Temporal Imaging


Dr. Derek Chang


Ultrashort pulses are regularly used to study ultrafast phenomena in all types of materials. Temporal imaging can be used to measure ultrafast waveforms in a single shot. It is a waveform manipulation technique that enables the expansion, compression, and even Fourier transforming of an input field in time while preserving the fidelity of the overall profile. Like any spatial imaging system, such as a camera or microscope, the performance of the entire system is highly dependent on the quality of its lens. Aberrations in the lens will cause artifacts and generate a distorted image at the output of the system. My research focuses on the design, fabrication and characterization of the time lens component of the system which is implemented using parametric interactions in a nonlinear medium. The phase of the incoming signal is modulated through sum-frequency generation with a chirped pulse in a Reverse Proton Exchanged (RPE) A-Periodically Poled Lithium Niobate (APPLN) waveguide device. This nonlinear optical frequency mixing component is central to how the time lens technology works and its performance is critical to the overall system performance.