What are the main bases of nonlinear optical materials?



The selection of nonlinear optical materials is mainly based on the following aspects: 1. This is basic, but not the only requirement. Because the laser power can reach a very high level, even if the nonlinear polarizability is not very large, the nonlinear optical effect can be enhanced by increasing the incident laser power; ② It has proper transparency and enough optical uniformity, that is to say, the harmful absorption and scattering loss of the material to light are very small in the frequency band of laser operation; ③ Phase matching can be achieved in a certain way (see optical phase conjugation); ④ The damage threshold of the material is high, and it can bear large laser power or energy; ⑤ There is an appropriate response time to make enough response to pulse laser or continuous laser with different pulse width.