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International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials)

Evolution of Von Neumann Entropy Across Electromagnetic Time Interfaces

M. S. Mirmoosa

Published Sep 1, 2025• 0 citations
Publisher

Abstract

Temporal modulation of materials offers unprecedented control over light, sparking recent interest in the quantum theory of light interaction with time-varying materials. In this presentation, through the lens of quantum optics, we evaluate the von Neumann entropy transformation induced by an electromagnetic time interface, in which the refractive index of an isotropic, homogeneous, nondispersive dielectric medium uniformly undergoes an abrupt change in time. We demonstrate that the entropy increases across such an interface, with the magnitude of the increase correlating positively with the refractive index contrast. Additionally, we analyze how photon population in the incident modes governs entropy evolution. We hope that our study advances both the fundamental physics of time interfaces and their potential applications in quantum information technology.

DOI
10.1109/metamaterials65622.2025.11174165

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