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Updated: May 11, 2025

Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Bright and Dark States of Light: The Quantum Origin of Classical Interference
Celso J Villas-Boas1, Carlos E Máximo1,2, Paulo J Paulino1,3
1Universidade Federal de São Carlos, Departamento de Física, 13565-905 São Carlos, São Paulo, Brazil.
Abstract:
Classical theory asserts that several electromagnetic waves cannot interact with matter if they interfere destructively to zero, whereas quantum mechanics predicts a nontrivial light-matter dynamics even when the average electric field vanishes. Here, we show that in quantum optics, classical interference emerges from collective bright and dark states of light, i.e., particular cases of two-mode binomial states, which are entangled superpositions of multimode photon-number states. This makes it possible to explain wave interference using the particle description of light and the superposition principle for linear systems only. It also sheds new light on an old debate concerning the origin of complementarity.
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