Discovery reveals a new type of organization in materials and expands our understanding of how complex structures emerge in nature

For the first time, scientists have observed a three-dimensional woven structure forming naturally inside a crystal, revealing a previously unknown way in which matter can organize itself.

Published in Light: Science & Applications, the study reports the observation of a three-dimensional woven fabric of interlaced nano-dipole ensembles that emerges spontaneously in a ferroelectric crystal as it cools through its phase transition. Unlike conventional ferroelectric crystals, in which ferroelectric domains consist of aligned electric dipoles, the dipoles in this material spontaneously weave over and under one another, creating an intricate three-dimensional network that resembles woven fabric. a type of organization never before observed in a solid crystal.

The researchers also found that they could change small parts of the woven network using a tightly focused green laser. The light locally untangles the woven pattern without affecting the rest of the crystal. Heating the crystal and cooling it again restores the woven structure, but with a new pattern.

The international research team consisted of a synergy between three research groups that employed several advanced imaging techniques. The groups were led by Prof. Eugenio Del Re of Sapienza University of Rome, Prof. Feifei Xin of Nankai University, and Prof. Aharon J. Agranat of the Institute of Applied Physics at the Hebrew University of Jerusalem, together with colleagues from the University of Groningen.

The phenomenon was observed in specially grown KTN:Li (KLTN) crystals invented by Prof. Agranat, in which periodic variations in the chemical composition were introduced during the crystal growth, forming striation gratings. These crystals were invented originally by Prof. Agranat for implementing electroholographic photonic switching, but were found here to be a platform for a new state of matter.

The researchers believe the discovery could represent a broader physical principle. Because the woven network forms through spontaneous symmetry breaking, they suggest that similar topological structures may emerge in many other systems, from liquid crystals and superconductors to quantum materials.

The authors said: "This is the first time anyone has observed a woven structure emerging spontaneously inside a solid crystal. What makes it exciting is not only that it reveals a completely new form of organization in matter, but that it suggests we may have overlooked similar topological structures in many other physical systems. Sometimes nature is far more creative than our theories predict."