Optimizing weak measurements to detect angular deviations

TL;DR

This paper investigates how to optimize weak measurements to enhance the detection of angular deviations of optical beams interacting with a dielectric prism, especially near critical and Brewster angles.

Contribution

It provides analytic expressions for angular deviations and compares direct measurement and weak measurement techniques to optimize amplification near critical and Brewster angles.

Findings

Weak measurements can preserve giant angular shifts near critical angles.

Direct measurements are more effective near Brewster angles.

Optimization conditions depend on incidence angles and wave polarization.

Abstract

We analyze and compare the angular deviations for an optical beam reflected by and transmitted through a dielectric triangular prism. The analytic expressions derived for the angular deviations hold for arbitrary incidence angles. For incidence approaching the internal and external Brewster angles, the angular deviations transverse magnetic waves present the same behavior leading to the well-known giant Goos-Haenchen angular shift. For incidence near the critical angle a new region of large shift is seen both for transverse magnetic and transverse electric waves. While a direct measuring procedure is better in the vicinity of the Brewster region, a weak measurement breaks off the giant Goos-Haenchen effect, preserving the amplification in the critical region. We discuss under which conditions it is possible to optimize the amplification and we also determine when a weak measurement is preferred to a direct measuring procedure.