Materials with Large Nonlinear Optical and Electro-Optical PerformanceID# 2022-5397
The inventors successfully grew large high-quality crystals having a chalcopyrite structure using a novel synthesis method that avoids using toxic chemicals. The uniaxial crystals exhibit a giant SHG coefficient of ~70pm/V at the fundamental wavelength of 1550nm, which is much larger than the commercial infrared NLO crystals and other NLO materials with the same bandgap. The crystals show excellent application value in frequency conversion such as frequency doubling, sum frequency, difference frequency, and down conversion in the IR laser system. Second-order optical nonlinearities showing a clear quadratic dependence on the input power confirmed the second order NLO effect. Third-order nonlinearities leading to the third harmonic generation and nonlinear absorption and nonlinear refraction are also superior, with fourth and even higher order nonlinearities expected to be large.
Application & Market Utility
This family of crystals exhibit superior electro-optic coefficients that promise orders of magnitude improvement in energy efficiency. This discovery may make nonlinear optical switching a compelling technique in photonic signal processing. These novel IR NLO crystals with superior optical properties have potential utility for next generational infrared laser system with wide tunability and high efficiency for broad applications such as communications, sensing and spectroscopy, including environmental monitoring, countermeasure, and laser surgery
The researchers are exploring other synthesis methods to grow cm-sized single crystals, including from additional compounds within this family. Millimeter sized samples of these crystals and polycrystalline materials may be available to evaluate.