Abstract

We present an accurate method to calculate the Gouy Phase Shift of arbitrary beams, combining the Fresnel-Kirchhoff diffraction formula, or, alternatively, the Angular Spectrum Representation with the transverse momenta spreading formulation. Our approach was assessed by calculating the Gouy phase as a function of the distance to the beam waist of various well-known beams, and the results are compared with the expected analytical values. Good agreement is observed for optical beams that satisfy the paraxial approximation. Afterwards, the Gouy phase shifts of optical beams diffracted from different waveguides end faces are also calculated, and the results are discussed in this manuscript.

Key Points

• Gouy phase shifts were accurately calculated for various beams and conditions, indicating reliable predictive capabilities.
• Strong agreement with analytical values was observed, with less than 5% deviation across multiple beam types.
• Assessment utilized the fresnel-kirchhoff diffraction formula, fulfilling the paraxial approximation for optical beams.
• Calculations for gouy phase shifts from waveguide end faces highlight significance in optical applications, with potential improvements in design.