Experimental investigation of wave-particle duality relations in asymmetric beam interference

TL;DR

This paper experimentally tests and compares quadratic and linear wave-particle duality relations in asymmetric photon interference, revealing differences in obtainable path information and enhancing understanding of quantum duality.

Contribution

First experimental verification of the linear wave-particle duality relation in asymmetric beam interference using photon polarization as a which-way detector.

Findings

Quadratic duality relation yields more path information.

Both duality relations are experimentally confirmed.

Differences between quadratic and linear forms are elucidated.

Abstract

Wave-particle duality relations are fundamental for quantum physics. Previous experimental studies of duality relations mainly focus on the quadratic relation $D^2+V^2\leq1$, based on symmetric beam interference, while a linear form of the duality relation, predicated earlier theoretically, has never been experimentally tested. In addition, the difference between the quadratic form and the linear form has not been explored yet. In this work, with a designed asymmetric beam interference and by utilizing the polarization degree of freedom of the photon as a which-way detector, we experimentally confirm both forms of the duality relations. The results show that more path information is obtained in the quadratic case. Our findings reveal the difference between the two duality relations and have fundamental implications in better understanding these important duality relations.