07-25-2023-0051 - The technique has been extended to optical frequencies in optical parametric oscillators and amplifiers which use nonlinear crystals as the active element. (DRAFT) ; This system of linear differential equations with constant coefficients can be decoupled and solved by eigenvalue/eigenvector methods. (DRAFT)

The technique has been extended to optical frequencies in optical parametric oscillators and amplifiers which use nonlinear crystals as the active element. 

https://en.wikipedia.org/wiki/Parametric_oscillator

This system of linear differential equations with constant coefficients can be decoupled and solved by eigenvalue/eigenvector methods.

https://en.wikipedia.org/wiki/Parametric_oscillator