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Emergence of an Epsilon-Near-Zero Medium from Microscopic Atomic Principles

L. Ruks1 and J. Ruostekoski2

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Phys. Rev. Lett. 135, 233603 – Published 4 December, 2025

DOI: https://doi.org/10.1103/qmx7-fvnk

Abstract

We demonstrate that an effective near-zero refractive index can emerge from collective light scattering in a discrete atomic lattice, using essentially exact microscopic simulations. In a 25-layer array, cooperative response leads to over a thirtyfold increase in the effective optical wavelength within the medium, almost eliminating optical phase accumulation, with potential applications in spectroscopy and optical manipulation of quantum emitters. Crucially, the near-zero refractive index arises from first-principles microscopic theory, rather than being imposed through continuous phenomenological effective-medium models—providing conceptually important insight into the emergence of macroscopic electromagnetism from atomic-scale interactions.

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Phys. Rev. Lett. 135, 233603– Published 4 December, 2025
  • Received 16 June 2025
  • Accepted 17 November 2025
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