Photonic Snakes, A New Instrument To Reveal The Secrets Of Light

UPC researcher Salim B. Ivars, PhD student at the Department of Physics at the UPC, has participated, together with research staff from the Institute of Photonic Sciences (ICFO) and the Universitat Politècnica de Valencia (UPV), in the discovery of the so-called 'Photonic snake states', a new instrument that can be of great help in revealing the secrets of light. The results of this research led by the UPV have been published in the scientific journal Nature Photonics.

Light, with its countless colors, is one of the wonders of nature. To really understand what we see it is essential to know the color of light with which we perceive our world. We achieved this through optical rules called frequency combs ( frequency combs in English), whose application deserved the Nobel Prize in Physics in 2005.

With optical rules, not only colors are measured, but also time, distances and other essential quantities; for this reason its importance in scientific and technological applications is enormous. They are the tools that allow you to enter the realm of light and reveal its deepest secrets. A further step is precisely what a recent study led by the Polytechnic University of Valencia (UPV), in which the researcher Salim B. Ivars, a student of the doctoral program in Computational and Applied Physics , participated , linked at the Physics Department of the Universitat Politècnica de Catalunya - Barcelona Tech (UPC), and Lluís Torner , director of theInstitute of Photonic Sciences (ICFO) , of the UPC. Yaroslav V. Kartashov, researcher at the Institute of Spectroscopy of the Russian Academy of Sciences (Moscow), has also participated.

In their work, published in the scientific research journal Nature Photonics , they have discovered the Photonic snake states , a new instrument to reveal, even more, the secrets of light, given that it opens unprecedented perspectives in the formation of frequency combs: predicts the existence of two-dimensional optical rules, more complex than the one-dimensional ones handled so far, and provide unprecedented versatility in a wide range of applications. The study has caught the attention of the international scientific community.

Applications in communications, spectroscopy, or computing
The uses of frequency combs are very varied, and they stand out above all in the field of communications. As the authors of the study explain, these combs allow large amounts of information to be transmitted through optical fibers in a very efficient way, since, by having well-defined frequencies, multiple light signals can be sent at the same time and separated easily when received.

Another area where frequency combs have shown great utility is in spectroscopy. By being able to obtain optical spectra with unprecedented precision and resolution, the identification of different substances is facilitated. This has direct application in fields such as chemistry, biology, and medicine, where detection requires molecules and characterization of materials is critical.

In the case of metrology, the science of measurement, these structures are used as a reference to define standards, thanks to their ability to generate stable and known frequencies. This allows for very precise measurements of fundamental quantities such as time or length, relevant to most scientific fields.

Finally, frequency combs have also found promising applications in quantum computing, where light particles (or photons) play a fundamental role. In particular, frequency combs can be used to generate single photons with specific properties, which is crucial for the development of these technologies.

The future of optical rules
A fundamental problem that needs to be analyzed in order to succeed in these proposals is that of the instabilities that appear when trying to build these optical rules and that prevent the generation of versatile forms of light. As Professor Pedro Fernández de Córdova , researcher at the IUMPA of the UPV and co-author of this work, points out, "it should be noted that our team has obtained, from a theoretical point of view, the conditions so that the structure of light is stable, finding zigzag-shaped configurations that we have called Photonic Snakes. The stability of these light states is a crucial aspect for future applications."

Likewise, in this article it has been shown that it is possible to create a two-dimensional arrangement of optical rules synchronized with each other and individually accessible. This discovery provides a large collection of rules generated in a single device and controlled by a single laser light source. In fact, as stated by Professor Carles Milián , responsible for this research: "the potential impact of this advance is extraordinary, since it could allow the development of reconfigurable, broadband multi-comb monolithic devices. These devices would provide different frequency combs on demand and in real time, significantly expanding existing applications”.

Finally, this study has been based on rigorous and very complete theoretical models, which have taken into account all known effects that could appear in future two-dimensional frequency comb formation experiments, and which have been simulated using powerful theoretical tools and numerical In fact, as pointed out by professor J. Alberto Conejero , director of the Department of Applied Mathematics at the UPV and co-author of this work, "in this research a very precise model has been built that includes all the phenomena that can influence the formation of these structures. It will work as a guide for future experiments, with the consequent economic impact of knowing in advance the experimental parameters with which stable light snakes can be generated."

According to the director of the ICFO, Lluís Torner " this important discovery is remarkable because it is unexpected and surprising, and has been possible thanks to the intuition and leadership of Professor Milián".

The UPV, UPC and ICFO team assures that this finding will further stimulate research in the field and lead to revolutionary new applications and technologies. "Thanks to these advances, we are one step closer to unraveling the mysteries of light and harnessing its full potential for the benefit of our society" , they conclude.