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TAU: The Electronics of the Future & World-Scale Archaeological Discovery

The electronics of the future: A new nanometer-scale graphene switch that operates with almost no energy

The Super-Lubric Array of Polytypes (SLAP) device in action. The bright and dark circles represent high and low electrical currents.

By applying just a tiny amount of pressure with a microscopic tip – similar to clicking a tiny ballpoint pen – the “islands” switch between states (R and B types), changing their brightness and electrical flow.  Credit: Tel Aviv University

A team of researchers from Tel Aviv University, in collaboration with colleagues from Japan, has taken an important step toward the next generation of electronics. The scientists achieved highly precise control of the internal structure of graphene — an exceptionally thin and strong material — using a minute, nearly negligible amount of energy.

 

The study was conducted under the supervision of Prof. Moshe Ben-Shalom of the School of Physics and Astronomy, together with Prof. Michael Urbakh and Prof. Oded Hod of the School of Chemistry. The experiments and calculations were led by Dr. Nirmal Roy and Dr. Pengua Ying, supported by Simon Salleh Atri, Yoav Sharaby, Noam Raab, and Dr. Youngki Yao. The findings were published in the journal Nature Nanotechnology.

 

Graphene, which consists of a thin layer of carbon atoms, has long been regarded as a “star” in the world of materials. Yet it is not only the material itself that matters, but also how the graphene layers are stacked on top of one another. Different stacking arrangements create entirely different properties: different electrical conductivity, different responses to magnetic fields, and even conditions that enable the emergence of superconductivity.

 

Until now, controlled switching between these stacking arrangements has been a complex process that required a great deal of energy and was unsuitable for practical applications. In the new study, the researchers succeeded in overcoming this obstacle.

The solution they developed is based on an elegant concept: creating tiny “islands” of graphene — only tens of nanometers in diameter — where the layers remain in direct contact with one another, while the surrounding areas are separated by a layer that allows nearly frictionless sliding. Within these islands, one graphene layer can be shifted relative to another, thereby changing the stacking arrangement.

 

The result is striking: the material’s state can be changed using an extremely small force, with an energy input orders of magnitude lower than that required by existing memory technologies. In many cases, once the change is initiated, it continues on its own, without the need to apply additional force.

 

Beyond this, the researchers showed that neighboring islands can be connected so that a structural change in one island also affects its neighbors. This opens the door to creating systems in which different regions “communicate” with one another in a mechanical-elastic manner, similar to a neural network. Such a property may be particularly relevant to the development of neuromorphic computing — computers that mimic the way the brain operates.

According to the researchers, the new method opens promising avenues for the development of memory components, sensors, and tiny electronic devices that are both fast and exceptionally energy-efficient. In the future, it may enable the creation of smart electronic systems on the nanometer scale — systems that consume less energy, generate less heat, and can perform complex operations in ways that until now seemed purely theoretical.

 

Prof. Moshe Ben-Shalom concludes: “This is a breakthrough that has the potential to transform the way electronic components are designed at the nanometer scale. We show that it is possible to control the structure of graphene and other layered crystals in a precise, reversible, and extremely energy-efficient manner. Instead of breaking and rebuilding chemical bonds, we simply slide atomic layers over one another — a natural process that is much faster and more efficient. The ability to design interactions between different regions within a material opens up new possibilities, not only for advanced electronics but also for brain-inspired computing systems. This is another step toward turning physical phenomena that until now were considered purely academic into practical, working technology.”

 

World-scale archaeological discovery in the Sakhnin Valley, Israel:

Findings dating back hundreds of thousands of years reveal
rare evidence for aesthetics and cognition among early humans

A Tel Aviv University Archaeologist and a resident of the Arab city of Sakhnin recently led an exceptional archaeological discovery in the Lower Galilee Sakhnin Valley, shedding new light on the cultural and cognitive world of our early ancestors. A surface survey revealed a series of Paleolithic sites containing hundreds of handaxes — large, carefully crafted stone tools — identified with Homo erectus, the early human species that lived in the region hundreds of thousands of years ago. Beyond the impressive quantity, however, the most noteworthy and unique find is an unprecedented concentration of handaxes shaped deliberately around fossils and distinctive geological features — a phenomenon almost unknown from other sites around the world. The study appeared in the prestigious journal published by the Sonia & Marco Nadler Institute of Archaeology, Entin Faculty of Humanities: Tel Aviv: Journal of the Institute of Archaeology of Tel Aviv University.

 

The sites in the Sakhnin Valley were identified by Muataz Shalata, a self-taught nature enthusiast from the city of Sakhnin, who noticed unusual knapped stones scattered across the terrain.  He contacted Prof. Ran Barkai of the Elkov Department of Archaeology at Tel Aviv University, an expert in the study of early Paleolithic cultures. Together, they are leading an innovative study focusing on human behaviors that evolved in the Sakhnin Valley hundreds of thousands of years ago.

 

Prof. Barkai: “Handaxes served as the main tool of early humans for more than a million years, and are known from Africa, Asia, and Europe. In the Sakhnin Valley, many hundreds of handaxes were found, indicating that the area served as an important hub of human activity over long periods of time. Providing early humans with all their needs – water sources, game, and an exceptional abundance of high-quality flint nodules — the area probably attracted human groups repeatedly over hundreds of thousands of years”.

 

“The Valley is also very rich in geodes – rounded, brain-like geological concretions containing sparkling crystals, as well as flint nodules embedded with fossil remains. Early humans who came here hundreds of thousands of years ago must have been astonished by this exceptional richness of stones, leaving behind them an extraordinary phenomenon: we have discovered more than ten handaxes fashioned from flint nodules containing fossils or special geological formations, with these natural features deliberately preserved in a prominent position at the center of each handaxe. Since such features make precise and symmetrical knapping difficult, we can conclude that the selection of these specific stones was not accidental. On the contrary — the knapping process highlighted the natural feature and kept it at the center of the tool.”

 

According to the researchers, this unique phenomenon clearly demonstrates aesthetic and conceptual intention among early humans, beyond functional considerations of tool production. Embedded fossils and geological formations do not improve the tool’s performance and may even impair it, yet such stones were repeatedly preferred as raw material. The conscious choice to invest effort in shaping a tool around an exceptional natural feature indicates that beyond survival needs, humans attributed special value to the stones’ appearance and meaning. Knapping served as a means for framing, highlighting, and enhancing intriguing natural phenomena, reflecting advanced perceptual and cognitive abilities.

 

The researchers also note that the Sakhnin Valley is located near presumed routes of early elephants, which were a primary food source for humans during this period. Thus, as at other prehistoric sites such as Gesher Bnot Ya‘akov, the handaxes were probably used to cut up elephants and extract calories from their fat and meat. However, such a high concentration of special handaxes is unknown in any other site worldwide, exceeding all comparable finds documented to date.

 

Prof. Barkai concludes: “The unique landscape of the Sakhnin Valley led early humans to behave in a distinctive manner. Apparently, they attributed great significance to the fossils and special geological features they found in the Valley, regarding them as manifestations of the potency, primordiality, and wonder of the cosmos. The integration of fossils and geological features endowed the handaxes with added potency and meaning, connecting them to primeval elements. The findings from the Sakhnin Valley open a rare window into the inner world of early humans, indicating that already at the dawn of human history they were sensitive to aesthetics, attributed meaning to nature, and had complex relationships with their world. The discovery places the Sakhnin Valley and the Lower Galilee at the heart of the international scholarly discussion on the origins of cognition, aesthetics and meaning in human life.”Top of Form

TEL AVIV UNIVERSITY

https://english.tau.ac.il/