Single-photon interferometry with orbital angular momentum circumvents standard wave-particle duality

TL;DR

This paper demonstrates that using polarized photons with orbital angular momentum in a Mach-Zehnder interferometer can bypass traditional wave-particle duality constraints, enabling simultaneous which-path information and high phase sensitivity.

Contribution

It introduces a novel interferometric scheme with orbital angular momentum that challenges the standard wave-particle duality limits.

Findings

Non-sinusoidal interferometric pattern observed

Simultaneous which-path information and phase sensitivity achieved

Potential for enhanced quantum measurement techniques

Abstract

A polarized photon with well-defined orbital angular momentum that emerges from a Mach-Zehnder interferometer (MZI) is shown to circumvent wave-particle duality. Its polarization-resolved detection probability forms a non-sinusoidal interferometric pattern. For certain phase differences between the MZI arms, this pattern yields both reliable which-path information and high phase-sensitivity.