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NOVIDADES
Researchers at MIPT Laboratory of Terahertz Spectroscopy together with their Russian and international colleagues discovered a new phase of nanoconfined water; separate water molecules that are confined within nanocavities formed by ions of the cordierite crystal lattice. The first reliable experimental observation of a phase transition in a network of dipole-dipole coupled water molecules is, in and of itself, an important fundamental breakthrough. But apart from that, the discovered phenomenon can also find practical applications in ferroelectrics, artificial quantum systems, and biocompatible nanoelectronics. Moléculas de água em cristais. Crédito: Daria Sokol , MIPT
“We are searching for new phases of electric dipole lattice, i. e. an ensemble of an interacting point electric dipoles,” explained Mikhail Belyanchikov, one of the study’s initiators and a junior researcher at MIPT Laboratory of Terahertz Spectroscopy. “A great number of different magnetic dipole phases have been discovered but the research of material phases related not to magnetic but rather to point electric dipoles is still in its early stages. Moreover, electric dipole lattices are a type of ferroelectrics that may have promising microelectronic applications.” It is known that to experimentally realize a lattice of point electric dipoles is a challenging task. Usually, physicists use the so-called interferometric optical lattice a periodic structure of fields that are created as the result of laser beams interference. Ultracold atoms of materials to be studied are placed into the lattice points. But researchers at MIPT Laboratory of Terahertz Spectroscopy found a more efficient way. They place separate water molecules that possess a rather high electric dipole moment into a so-called dielectric matrix, in this case, a zeolite crystal lattice with periodically distributed nanoscale voids formed by lattice ions. One then gets an easily handled sample (a crystal) with practically free water molecules trapped (during crystal growth) in these voids the so-called nanoconfined water. This sample can be studied in a wide range of temperatures including room temperature and in different environments (electric fields, pressure, etc.). The key result of the study however was achieved at a rather low temperature of 3 K (270 °C). The studied electric dipole lattice of polar water molecules was based on a cordierite crystal a member of the zeolites family. The researchers observed an order-disorder ferroelectric phase transition in a three-dimensional nanoconfined water molecular network at the temperature of 3 K. Cordierite crystals.
To analyze and interpret experimental findings, researchers employed computer modeling. Monte Carlo simulation and other mathematical methods such as the numerical solution of the extremely complex multiparticle Schrödinger equation were used to describe the electric dipole system of interacting polar water molecules. “Not only does studying nanoconfined water molecules have fundamental importance for the field of electro-dipolar lattices but it also contributes to a deeper understanding of natural phenomena and may even potentially enable the construction of biocompatible nanoelectronic devices. This is a rapidly developing field that promises new and extremely efficient electronics based on biological materials,” comments Boris Gorshunov, who heads the MIPT Laboratory of Terahertz Spectroscopy. Read the original article on the Moscow Institute of Physics and Technology (MIPT). Statnano. Posted: August 20, 2020.
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