Aspects of the phenomenology of interference that are genuinely nonclassical

TL;DR

This paper investigates which aspects of quantum interference phenomena are truly nonclassical, demonstrating that the fundamental wave-particle duality relation cannot be explained by noncontextual models, thus highlighting its nonclassical nature.

Contribution

The paper proves that the wave-particle duality relation is inherently nonclassical by showing it cannot be reproduced in noncontextual models, unlike other interference aspects.

Findings

Wave-particle duality relation cannot be modeled noncontextually.

Noncontextual models can reproduce certain interference phenomenology.

The duality relation acts as a signature of quantum contextuality.

Abstract

Interference phenomena are often claimed to resist classical explanation. However, such claims are undermined by the fact that the specific aspects of the phenomenology upon which they are based can in fact be reproduced in a noncontextual ontological model [Catani et al., Quantum 7, 1119 (2023)]. This raises the question of what other aspects of the phenomenology of interference do in fact resist classical explanation. We answer this question by demonstrating that the most basic quantum wave-particle duality relation, which expresses the precise tradeoff between path distinguishability and fringe visibility, cannot be reproduced in any noncontextual model. We do this by showing that it is a specific type of uncertainty relation and then leveraging a recent result establishing that noncontextuality restricts the functional form of this uncertainty relation [Catani et al., Phys. Rev. Lett. 129, 240401 (2022)]. Finally, we discuss what sorts of interferometric experiment can demonstrate contextuality via the wave-particle duality relation.