Scientists in Japan have revealed that if a glassy solid possesses a planar (sheet-like) structure, it can exhibit enhanced thermal vibration motion due to the same mechanism known for the planar crystals (two-dimensional crystals), by using large-scale simulations on supercomputers.
"Imagine if we could make a sheet of glass, which has a two-dimensional (2D) planate shape," says Dr. Hayato Shiba, of Tohoku University's Institute for Materials Research (IMR). "In such a confined spatial dimension, a variety of novel phenomena takes place in usual "periodic" systems (crystals, spin systems etc.). This is due to the thermal motion of the constituents taking place on a larger scale because of the limited spatial dimensions."
Left and right figures are schematic diagrams of glassy solid in two and three dimensions. Modality of the dynamics of glassy solid in different dimensions is illustrated. In three dimensions, a particle vibrates inside a cage formed by neighboring particles, due to the densely packed condition of the particles, and intermittently goes out of the cage. In two dimensions, long-wavelength vibrational sound waves induce coherent motion of the particles with a large amplitude that can in principle exceed the length scale of particle radii (the aqua colored circle on the left indicates that the caged particle can move a large distance).
Credit: Hayato Shiba
Such enhanced thermal motion is known to induce new physical phenomena which Shiba, and his research team of Yasunori Yamada (IMR), Takeshi Kawasaki (Nagoya University) and Kang Kim (Osaka University), hope will lead the development of new functional materials and devices necessary for the realization of energy-saving societies.
However, it is still uncertain whether 2D glass, as an "non-periodic" system, exhibits such enhanced thermal motions.
"Our result indicates that 2D glass can become soft, gradually and forever, as we go to the macroscopic scales. Consequently, the vibration amplitude becomes infinite because of the large-scale motions," says Shiba.
"In other words, such materials might exhibit strong responses to external fields or deformation. The thermal vibration is perfectly different from that in a 3D glass, and it can even alter the fundamental nature of vitrification and glassy phase transition."
In the experiments, 2D glass was experimentally realized using colloidal systems, and can also be realized using other soft and hard materials.
Hayato Shiba | EurekAlert!
Let the good tubes roll
19.01.2018 | DOE/Pacific Northwest National Laboratory
Method uses DNA, nanoparticles and lithography to make optically active structures
19.01.2018 | Northwestern University
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
19.01.2018 | Materials Sciences
19.01.2018 | Health and Medicine
19.01.2018 | Physics and Astronomy