Abstract
Mid-infrared refers to electromagnetic waves in the wavelength range of 3-50 μm, thus the development of mid-infrared is important for the studies of chemistry, physics and biology. Optical parametric amplification (OPA) is a nonlinear optical effect that is commonly used to generate mid-infrared pulses. We have designed a simple OPA system pumped by a Ti:sapphire laser amplifier that produces 25 fs pump pulses at 1 kHz repetition rate with wavelength range centered at 800 nm. We have tapped a small part of energy of a pump pulse to generate a signal pulse centered at 1064 nm via white-light continuum. The idler pulses we have gotten by OPA are mid-infrared ultrashort pulses. This thesis explains how we chose the parameters of the nonlinear crystal, the theories of the mechanisms involved in the experiment, experimental setup, and the advantages of this OPA system in detail. In this thesis we have shown the numerical simulation and the experimental results to prove that we have successfully generated mid-infrared ultrashort pulses. Its wavelength range is centered at 3200 nm. If the mid-infrared pulses we generated are compressed properly in the future, its pulse duration will have a good chance to reach tens of femtoseconds.