Classical wave-optics interpretation of weak-measurement amplification for the Goos-Hänchen effect
Phys. Rev. A 113, 033528 – Published 27 March, 2026
DOI: https://doi.org/10.1103/s5c9-n7zp
Abstract
The Goos-Hänchen (GH) effect, a fundamental beam displacement phenomenon occurring during total internal reflection, has been challenging to utilize directly in high-sensitivity applications due to its inherently small, subwavelength scale. The weak measurements have been widely used to amplify this effect involving abstruse quantum interpretations. In this work, we present a clear and insightful classical wave-optics derivation and visualization of the weak-measurement amplification process for the GH effect from the perspective of optical differential interference. By leveraging the polarization-dependent lateral displacements induced by the GH effect, we demonstrate that the reflected field can be decomposed into a fundamental Gaussian component and a first-order differential component. Through coherent superposition using a simple polarizer, we establish an interferometric setup that directly converts the nanometer-scale GH shift into a micrometer-scale displacement of the output field centroid. Our model, derived entirely from classical electromagnetic theory and Fourier optics, provides a clear physical picture of the amplification mechanism. This work offers a versatile and powerful framework for precision measurement, nanophotonics, and interferometric sensing.
