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The Thinnest Mirror In The World Has Been Created

The Thinnest Mirror In The World Has Been Created

The mirror consists of only 200 atoms and is a thousand times thinner than a human hair, yet the reflection in it is of excellent quality and can be seen with the naked eye.

As a rule, for optical mirrors, polished metal surfaces or coated with a reflective glass composition are used, which give better quality with less weight. But physicists at the Max Planck Institute for quantum optics in Munich have shown a mirror that consists of a single structured layer of atoms.

The development is unique — it is one of the first experiments in the new field of research of sub-waves of quantum optics with ordered particles. Details are published in the journal Nature.

The new optical mirror is based on two parameters: the order of atoms and the distance between sub-wave frequencies. They suppress diffuse light scattering and combine reflection into a directed and steady beam. Due to the relatively close and discrete distance between the atoms, the photon can bounce off the particles more than once before it is reflected. Together, the effects give a strong reflection that can be seen with the naked eye.

This is the lightest and thinnest mirror in the world: it is only a few tens of nanometers thick, which is a thousand times thinner than a hair, and only seven micrometers in diameter. The development is unlikely to be used for commercial purposes in the near future — the mirror cannot yet be made large enough. In addition, the device in which it was created is huge: it has more than a thousand optical elements, and the weight is two tons.

However, the material has great potential for science. "The results are very interesting for us. On the one hand, photon-mediated correlations between atoms, which play a vital role in our system, are usually ignored in traditional theories of quantum optics. On the other hand, ordered arrays of atoms obtained by loading ultracold particles into optical lattices were mainly used to study quantum modeling of condensed matter. But they also proved to be a powerful platform for studying new quantum optical phenomena," explains Jun Rui, one of the authors of the paper.

Further research could deepen the understanding of quantum theories of the interaction of light and matter, as well as the physics of many bodies with optical photons, scientists believe. They also make it possible to create more efficient quantum devices.

"For example, the work provides a fascinating new approach to quantum optomechanics, a growing field that explores the quantum nature of light through mechanical means. It can also help create a better quantum memory or quantum switchable optical mirror," adds one of the authors of the paper, David Wei. — Both of them are interesting and would be a significant achievement on the way to the possibility of quantum transmission of information."