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arXiv · 2509.01702

Photon emission without quantum jumps

Thomas Hartwell·Daniel Hodgson·Huda Alshemmari·Gin Jose·Almut Beige
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Abstract

When modelling photon emission, we often assume that the emitter experiences a random quantum jump. When a quantum jump occurs, the emitter transitions suddenly into a lower energy level, while spontaneously generating a single photon. However, this point of view is misleading when modelling quantum optical systems which rely on far-field interference effects for applications like distributed quantum computing and non-invasive photonic quantum sensing. In this paper, we highlight that the dynamics of an emitter in the free radiation field can be described by simply solving a Schroedinger equation based on a locally-acting Hamiltonian without invoking the notion of quantum jumps. Our approach is nevertheless consistent with quantum optical master equations.

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Thomas Hartwell, Daniel Hodgson, Huda Alshemmari, Gin Jose, Almut Beige. 2026-01-08. Photon emission without quantum jumps. https://doi.org/10.1088/1367-2630%2Fae33e2

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