MATLAB Implementation of Nonlinear Fiber Optics with Self-Phase Modulation (SPM) Code

Nonlinear fiber optics is a field studying nonlinear effects in optical fibers, with self-phase modulation (SPM) being one of the important phenomena. SPM causes phase changes in optical signals through nonlinear effects, thereby affecting signal transmission and modulation. This implementation provides MATLAB code for nonlinear fiber optics and SPM to help better understand and apply these concepts. The code typically involves solving the nonlinear Schrödinger equation using split-step Fourier methods, where key functions include: - Numerical integration of nonlinear phase accumulation - Implementation of dispersion effects using frequency domain operators - Power-dependent refractive index calculations - Optical field propagation through iterative steps Core algorithm components feature: - Time-domain to frequency-domain transformations via FFT - Nonlinear phase shift computation: φ_NL = γ * P * L_eff - Step-size adaptive propagation for numerical stability - Visualization modules for observing spectral broadening effects The implementation demonstrates how SPM induces spectral broadening and pulse shaping through MATLAB's computational capabilities, making it suitable for educational and research applications in photonics and optical communications.