Transparency on demand: Lifting the fog at the push of a button
Induced transparency: The precise control of the energy flow (indicated by glowing particles in the fog) makes the artificial material become entirely transparent for the optical signal. Credit: Andrea Steinfurth / University of Rostock

The final frontier is space. When all communication channels are suddenly cut off, the starship Enterprise is pursuing its mission. In many episodes of the beloved TV series, the crew must quickly tech the tech and science the science in order to escape from a similar situation before the end credits roll. A team of scientists from the University of Rostock have succeeded in developing an entirely new approach for the design of artificial materials that can transmit light signals without any distortions by means of precisely tuning flows of energy. Their results have been published.

Light spreads in an inhomogeneous medium. Professor Alexander Szameit of the Institute for Physics at the University of Rostock describes the starting point of his team's work. The specifics of scattering are determined by the distribution of the material's microscopic density. The idea of inducing transparency is to use a lesser-known optical property to clear a path for the beam.

The second property is known as non-Hermiticity and describes the flow of energy, or more precisely, the amplification and attenuation of light. The fading of a light beam due to absorption would seem counter-productive to the task of improving signal transmission. Non-Hermitian effects have become a key aspect of modern optics, and an entire field of research strives to harness the sophisticated interplay of losses and amplification for advanced functions.

This approach opens up completely new possibilities, according to the first author of the paper. To counteract any degradation of a beam of light, it is possible to amplify or suppress certain parts of it. Steinfurth says that they are modifying a material to tailor it for the best possible transmission of a specific light signal. They were able to recreate and observe the tiny interactions of light signals with their newly developed active materials in networks of kilometer-long optical fibers.

Induced transparency is one of the fascinating possibilities that arise from these findings. The prevention of scattering is not enough if an object is to be made to disappear. Light waves must not come behind it. Diffraction alone ensures that any signal will inevitably change its shape, even in the vacuum of space. Not even the fictional cloaking devices of the Romulans can do that, according to co-author Dr.

The findings presented in this work represent a breakthrough in fundamental research on non-Hermitian photonics and provide new approaches for the active fine-tuning of sensitive optical systems. Other potential applications include the synthesis of versatile artificial materials with tailored properties.

More information: Andrea Steinfurth et al, Observation of photonic constant-intensity waves and induced transparency in tailored non-Hermitian lattices, Science Advances (2022). DOI: 10.1126/sciadv.abl7412 Journal information: Science Advances Citation: Transparency on demand: A novel process can render artificial materials transparent or even entirely invisible (2022, May 31) retrieved 31 May 2022 from This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.