KEYWORDS: Second harmonic generation, Sum frequency generation, Third harmonic generation, Phase matching, Difference frequency generation, Simulations, Nonlinear crystals, Nonlinear dynamics, Gaussian pulse, Gallium arsenide
Third harmonic generation (THG) achieved by the simultaneous phase matching of multiple quadratic nonlinear processes in a single crystal has been studied previously both theoretically and experimentally, achieving modest conversion efficiencies. As opposed to the common practice of using second harmonic generation (SHG) and sum frequency generation (SFG) stages in series, performing these processes in parallel results in a narrow material parameter range in which the transfer of energy to the third harmonic can be fully efficient, even under conditions of perfect phase matching. This is largely due to the presence of back-conversion in the conversion dynamics, which limits the efficiency for spatio-temporally non-uniform beams. Here we demonstrate an unconventional method of THG where the fundamental wave is first frequency-quadrupled through cascaded SHG before being down-converted to the third harmonic. When the three associated phase matching conditions are met simultaneously, we find that energy is transferred robustly and efficiently from the fundamental wave to the third harmonic with inhibited back-conversion. This is an example of convergent dynamical behavior emerging from hybridized nonlinear optical processes as recently observed in hybridized parametric amplification. These dynamics are achievable over a broad parameter range that correspond to common nonlinear crystals. Using a spatio-temporal numerical investigation, we find that 25-ps CO2 laser pulses with Gaussian spatio-temporal profiles and 10-μm wavelength can be converted to their third harmonic with over 80% conversion efficiency in a realizable monolithic orientation-patterned GaAs device. High performance realizable domain-poled KTP and LNB devices are also investigated.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.