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What do ultrasound imaging of a fetus, cellular mobile communication, micro motors, and low-energy-consumption computer memories have in common? All of these technologies are based on ferroelectric materials, which are characterized by a strong correlation between their atomic structure and the electrical and mechanical properties.

Technion – Israel Institute of Technology researchers have succeeded in changing the properties of ferroelectric materials by vacating a single oxygen atom from the original structure. The breakthrough could pave the way for the development of new technologies. The research was headed by Assistant Professor Yachin Ivry of the Department of Materials Science and Engineering, accompanied by postdoctoral researcher Dr. Hemaprabha Elangovan and Ph.D. student Maya Barzilay, and was published in ACS Nano. It is noted that engineering an individual oxygen vacancy poses a considerable challenge due to the light weight of oxygen atoms.

Asst. Prof. Yachin Ivry

In ferroelectric materials, a slight shift of the atoms causes significant changes in the electric field and in the contraction or expansion of the material. This effect is the result of the fact that the basic repeating unit in the material contains atoms that are organized in an asymmetric structure.

In order to explain this further, the researchers use the seminal ferroelectric material, barium titanate, the atoms of which form a cubic-like lattice structure. In these materials, a unique phenomenon occurs: the titanium atom draws away from the oxygen atoms. Since titanium is positively charged and oxygen is negatively charged, this separation creates polarization, or in other words, an electric dipole moment.

A cubic lattice has six faces, so the charged atoms move into one of six possibilities. In different parts of the material, a large number of neighboring atoms shift in the same direction, and polarization in each such area, which is known as a ferroelectric domain, is uniform.

Traditional technologies are based on the electric field created in those domains. However, in recent years, a great deal of effort has been directed at minimizing the device size and using the borders, or walls, between the domains rather than the domains themselves, and thus converting the devices from three-dimensional structures to two-dimensional structures.

Dr. Hemaprabha Elangovan, Asst. Prof. Yachin Ivry and Ph.D. student Maya Barzilay

The research community has remained divided in opinion as to what happens in the two-dimensional world of the domain walls: How is the border between two domains with different electric polarization stabilized? Is the polarization in domain walls different to the polarization in the domains themselves? Can the properties of the domain wall be controlled in a localized manner? The great interest in addressing these questions stems from the fact that a ferroelectric material in its natural form is an excellent electric insulator. However, the domain walls may be conducting electrically, thus forming a two-dimensional object that are controllable by will. This phenomenon encompasses the potential to reduce significantly the energy consumption of data storage and data processing devices.

In this project, the researchers succeeded in deciphering the atomic structure and electric field deployment in domain walls at the atomic scale. In their recent article, they corroborate the assumption that domain walls allow for the existence of a two-dimensional border between domains as a result of partial oxygen vacancy in areas that are common to two domains, thus enabling greater flexibility in the deployment of the local electric field. They succeeded in engineeringly inducing an individual oxygen atom vacancy and demonstrated that this action creates opposing dipoles and greater electric symmetry – a unique topological structure called a quadrupole.

With the aid of computer simulations by Shi Liu of Westlake University in China, the researchers demonstrated that engineering the oxygen atom vacancy has a great impact on the electrical properties of the material not only at the atomic scale, but also at the scale that is relevant to electronic devices – for example, in terms of electrical conductivity. The significance is that the present scientific achievement is likely to be of help in miniaturizing devices of this kind as well as reducing their energy consumption.

In the micrograph: Image of the structure before (on the right) and after (left) removing an oxygen atom

In collaboration with researchers from the Negev Nuclear Research Center, the Technion research group also demonstrated that oxygen vacancies can be engineered by exposing the material to electronic radiation. Consequently, in addition to the technological potential of the discovery in electronics, it may also be possible to utilize the effect for radiation detectors, allowing for the early detection – and prevention – of nuclear accidents, such as the one that happened in 2011 in Fukushima, Japan.

The research, which was carried out at the Electron Microscopy Center in the Faculty of Materials Science and Engineering, was funded by the Israel Science Foundation and the Pazy Foundation. The Nano and Quantum Functional Structures Laboratory, headed by Asst. Prof. Ivry, is supported by the Zuckerman STEM Leadership Program.

For the article in ACS Nano click here

Researchers at the Technion – Israel institute of Technology, in collaboration with researchers from CNRS, recently published findings about the development of an artificial molecule that may inhibit the development of Alzheimer’s disease. The molecule breaks down the toxic chemical complex Cu–Aβ, thus inhibiting the cell death that is thought to be related to Alzheimer’s. The study was led by Professor Galia Maayan and doctoral student Anastasia Behar from the Schulich Faculty of Chemistry, in collaboration with Prof. Christelle Hureau from the Laboratoire de Chimie de Coordination du CNRS, Toulouse, France.

Prof. Galia Maayan

Copper ions are a key component of the structure and function of various cells in the body. But their accumulation can lead to cell toxicity, causing dangerous conditions such as oxidative stress, cardiovascular disorders, and degenerative diseases of the brain, including Alzheimer’s.

One of the mechanisms involved in the development of Alzheimer’s is the formation of free radicals that damage the brain cells. These are oxidizing agents formed, among other things, by Cu–Aβ, a complex of copper and amyloid beta.

It is already known that the breakdown of this complex, and the removal of copper from the amyloid, prevents cell death, followed by the inhibition of the disease. The extraction of the copper is done by chelation – using molecules that bind the copper ions and extract them from the amyloid.

Doctoral student Anastasia Behar

However, this is not a simple challenge, because the chelators must meet several critical chemical and kinetic conditions, including stability and resistance to oxidation-reduction reactions. It is also important that the chelator does not bind zinc ions during the copper extraction process, as they are also essential for neuron function (but do not cause toxicity when they are bound to the amyloid); if the chelator does not bind the zinc, it can continue to bind the copper ions, but if it binds zinc, copper binding will be inhibited.

The Technion and CNRS researchers report in the Angewandte Chemie on the successful development of a new artificial chelator that meets all these requirements. The chelator, called P3, is a peptide-like water-soluble synthetic molecule that performs its task selectively; it strongly binds copper and forms the complex CuP3, extracting the copper from the amyloid. By doing so, it inhibits and even suppresses the formation of harmful oxidizing agents, without creating new oxidation processes. Although it binds zinc ions and even extracts them from the amyloid faster than it extracts the copper ions, the binding to zinc is weaker, making the zinc-amyloid complex unstable, so in practice P3 mostly binds copper ions.

In the figure, from left to right: Oxidation of copper ions in an amyloid complex (that also contains zinc ions) leads to the formation of a toxic amyloid complex and harmful oxidizing agents (ROS). The water-soluble chelator extracts the copper ion from the amyloid complex by creating a new, stable complex, and inhibits the formation of harmful oxidizing agents (NO ROS), thereby neutralizing amyloid toxicity.

Click here for the paper in Angewandte Chemie

Technion researchers have presented an innovative method for the formation of nanowires. In it, the nanowires form within line defects that exist in metals. Such defects are known as dislocations. This is the first time that dislocation lines in a material of one kind serve as a template for the growth of a different inorganic material in the form of nanowires. The study, which was published in PNAS, was led by Professor Boaz Pokroy and Ph.D. student Lotan Portal of the Faculty of Materials Science and Engineering and the Russell Berrie Nanotechnology Institute.

Professor Boaz Pokroy

Dislocations are a significant phenomenon in materials science since they affect the material’s properties on both the macro- and microscales. For example, a high dislocation density increases a metal’s strength and hardness. The dislocation edges on metal surfaces and the atoms in their proximity tend to be more chemically activated compared to other atoms in the material and tend to facilitate various chemical reactions, such as corrosion and catalysis.

Lotan Portal

The researchers in Prof. Pokroy’s group created nanowires of gold-cyanide complex from classic Au-Ag alloy. In professional terminology, they synthesized inorganic gold(I)-cyanide (AuCN) systems in the shape of nanowires, using an autocatalytic reaction (i.e. through the acceleration of a reaction by one of its reactants). Gold-cyanide complex is used in numerous fields including ammonia gas detection (NH₃ sensors), catalysis (acceleration) of water-splitting reactions, and others.

In black and white: Scanning electron microscope image of a lateral section of a sample that contains a gold-cyanide nanowire created from Au-Ag (to a depth of 2 microns from the surface of the sample).

In the process developed by the researchers, nanowires crystallize at the dislocation ends on the surface of the original gold-silver (Au-Ag) alloy, and the final structure obtained is classic nanoporous (sponge-like) gold, with a layer of nanowires emerging from it. Formation of the nanowires occurs during the classic selective dealloying process that separates the silver from the system and forms the nanoporous gold and is achieved only when the dislocation density exceeds a critical value, as presented in the kinetic model developed and demonstrated in the article.

The model provides a possible route for growing one-dimensional inorganic complexes while controlling the growth direction, shape, and morphology of a crystal according to the original alloy’s slip system. As mentioned, this scientific and technological achievement has numerous potential applications.

In the figure: A schematic drawing depicting 1D nucleation and growth of a gold-cyanide nanowire along a dislocation in the original alloy during the classic selective dealloying process.

The research was sponsored by a European Research Council (ERC) Proof of Concept Grant (“np-Gold” project) as part of the Horizon 2020 Program.

For the article in PNAS click here

The first cohort graduated from the Guangdong Technion Israel Institute of Technology in a moving ceremony held earlier this week in China, where 149 students received their bachelor’s degrees.

GTIIT graduates

“GTIIT is the first and only endeavor of its kind in the mutual history of China and Israel,” Technion President Prof. Uri Sivan, who joined the ceremony via videoconferencing, said at the event. “Two ancient nations, which share the values of knowledge, scholarship, and innovation for thousands of years, have bridged across geography and language to create the marvel that we celebrate today. He went on to say that the language of science “bridges geographies and cultures to connect all people for the benefit of humanity. It is this language, that you, dear graduates, have acquired at GTIIT.”

נשיא הטכניון פרופ' אורי סיון מברך את הבוגרים בטקס מחיפה

Technion President Prof. Uri Sivan speaks at the first GTIIT commencement

Prof. Sivan congratulated the graduates, faculty, and leaders of GTIIT. He thanked Mr. Li Ka-shing, former GTIIT Chancellor Li Jiange, former Technion President Prof. Peretz Lavie, and the Technion Special Envoy to GTIIT, Nobel Laurette Distinguished Prof. Aaron Ciechanover. “The creation and success of GTIIT is the outcome of the work of many, both in Israel and in China,” Prof. Sivan said. “Still, we would not be here today without the profound vision, brilliant leadership, and deep devotion of these individuals to the idea, which is now a living fact.”

Prof. Gong Xingao, Chancellor of GTIIT, greeted the guests, graduates and faculty, and so did Technion faculty members Prof. Dganit Danino, and Prof. David Gershoni. Peleg Lewi, Consul General of Israel in Guangzhou, also spoke at the ceremony.

The Guangdong Technion-Israel Institute of Technology (GTIIT) was inaugurated in China. The project is the result of a historic partnership between the Li Ka Shing Foundation, the Guangdong Provincial Government, the Shantou Municipal Government and the Technion-Israel Institute of Technology.

To read the full story on the GTIIT website, click here.

To watch the entire graduation ceremony:

Photos and video courtesy of the GTIIT Office of News & Public Affairs

In a nano-optics breakthrough, Technion researchers observed sound-light pulses in 2D materials, using an ultrafast transmission electron microscope. The study, recording for the first time the propagation of combined sound and light waves in atomically thin materials, was published in the prestigious journal Science.

To read the full story and others – from Israel’s first visually impaired doctor to cutting-edge artificial intelligence research, click here.

New collaborations, cures, and game-changing discoveries from Technion Israel.

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The ambassador of the UAE to Israel, H.E. Mohamed Al Khaja, visited the Technion last week, expressing interest in joint research, particularly on water and food security. “Shared science and research will bring our countries and people closer,” he said during the historic visit.

“What sets us apart from other universities is that there is no other whose commitment to their country plays such a central role. Our founders perceived the Technion as the Jewish people’s university, a role we are proud to fulfill to this very day.” A special message from Technion President, Professor Uri Sivan, for Yom HaZikaron (Remembrance Day) and Yom Ha’Atzmaut (Independence Day).

The mysteries of the mind, Israel’s greatest exit and Technion and the Crown – all in the latest edition of Technion LIVE – hot technology news from Israel!
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“Your future is here”: 700 outstanding high school students take part in Tech Women at Technion this month.

“Your future is here,” announced computer science student Karen Yitzhak to the group of excellent female high school students attending this year’s Tech Women, which she hosted.

Arriving at Technion City from Israel’s four corners, the 700 female students are presently excelling in math and science at school. During the Tech Women even at Technion – Israel Institute of Technology the students met with researchers, faculty, and graduates, touring laboratories and encountering a range of research fields.

Tech Women events are held at the initiation of the Rosalyn August Women Girls Empowerment Mission (GEM) and are designed to inspire female students with the field of possibility and opportunity at Technion and to encourage them to pursue undergraduate studies in science and engineering.

Technion Vice President for External Relations and Resource Development Prof. Alon Wolf, who opened the event.

“Already in the Technion’s first class in 1924, the 17 students studied included one female. This was at a time when, in many countries, academia was closed to women. Since its first day, the Technion has received male and female students based on their abilities alone and regardless of religion, race and gender,” said Prof. Alon Wolf, Vice President for External Relations and Resource Development who opened the event. “You also came here to the Technion today because of your abilities. If you want to influence the future of the world and determine what it will look like in fifty years’ time, come study at the Technion.”

The opening event was hosted by student Keren Yitzhak, who began her studies at the Technion Preparatory Program some five years ago and will soon complete here bachelor’s degree in computer science. “You were selected to attend this event because you are brilliant, and we have no doubt that your future is here,” said Yitzhak, who in parallel to her studies works at Melanox. “Even if you aren’t sure what you want to do when you grow up, the Technion is a great starting point for you.”

Dr. Rotem Vishinkin, who received her PhD from the Technion this year, spoke about her path at Technion and about the studies she conducted under the guidance of Prof. Hossam Haick of the Wolfson Faculty of Chemical Engineering. In recent years, Dr. Vishinkin innovated a sticker to diagnose tuberculosis. The development, supported by the Bill and Melinda Gates Foundation

Host of the event, student Karen Yitzhak of the Faculty of Computer Science

and the European Union, is expected to save the lives of millions of people in developing countries through early diagnosis and compatible care. “As a young girl, I dreamed of becoming a doctor,” she told the students. “But in the end, I chose chemical engineering studies, where I combine engineering and life sciences. As the director of the Apatch group, where research partners from academia, hospitals and various companies are developing a sticker to diagnose tuberculosis, I feel that I’m making a unique and significant contribution to humanity.”

The Technion – Israel Institute of Technology salutes the Apollo 11 heroes who landed on the moon 50 years ago. Buzz Aldrin, who will soon be celebrating his 90th birthday, was an honored guest at Technion Israel during the International Space University, which held its international program at Technion City.

Buzz Aldrin at Technion in 2016

The first moon landing, starring Neil Armstrong and Buzz Aldrin, took place 50 years ago on July 20th, 1969. Armstrong descended from the lander to the moon, followed by Aldrin, who described the scene as a “spectacular wilderness” – a phrase he would later use as the title of his autobiography. The astronauts set up the US flag and a memorial plaque on the moon; carried out some pre-determined scientific missions; and spoke to the US President Richard Nixon. They then boarded the lander and returned to Columbia, the commanding cell, where Michael Collins, their colleague on the mission, was waiting for them all the time to orbit the moon. Apollo 11 began its journey back home. They positioned the flag of the United States of American on the moon, together with several other items, including greetings from 73 national leaders. One of these was from the President of the State of Israel, Zalman Shazar, who wrote: “From the President of Israel in Jerusalem, as long as there is a moon, there will be peace.”

Dr. Buzz Aldrin visited the Technion in 2016. In his lecture at the Technion, Dr. Aldrin said: “I have no doubt that I am lucky. My mother was born when the Wright brothers made the first flights in history, and my father was one of the pioneers of the aviation world. I just flew jets in the Korean War and made spacewalks, and yet I got to go on the moon.”

Dr. Aldrin, a graduate of West Point Military Academy and a former combat pilot, received his Ph.D. from MIT in 1963. He was accepted as an astronaut in 1963 and in the summer of 1969, he landed on the moon. “We got a chance to land on the moon, and the opportunity became a milestone, an event that changed the history of mankind,” he said in his lecture at the Technion. “Humanity has succeeded in setting foot in a new and entirely different place: 400,000 people have been involved in the success of this mission and half a billion have watched us in that historical event.”

Over the last three decades, Dr. Aldrin has invested most of his time in the mission of manning Mars. He established the Buzz Aldrin Space Institute in Florida to promote settlement on Mars, with the target year of 2040. “Mars is the island waiting for us in the dark of space: Get your Ass to Mars, because there, as President Kennedy said about the mission of landing on the moon, we have a connection with fate.”

This year, following the crash of the Israeli ship Bereshit, Aldrin tweeted to the project’s people: “Never despair – your efforts, your innovation and the work of your team are an inspiration to us all.”

Like his colleague, Neil Armstrong, the first man on the moon, was born in 1930. As a teenager, he worked hard to finance the flight rates that were his ultimate ambition, and at the age of 16, he received a pilot’s license. At the age of 20, he was a fighter pilot, and in the next two years, he performed almost 80 combat flights in Korea. In 1966, as a fresh astronaut, he saved himself and his crew after a dangerous mishap at Gemini 8.

Over the next three years, Armstrong gained extensive experience on the ground and in space and was eventually appointed the commander of the first moon landing mission, Apollo 11. And so on July 20, the voice in the control room said: “Here is the calm sea base. After performing all the steps required for the historic march, he reported this time to half a billion listeners and viewers: “A small step for man, a tremendous leap for mankind.” Four days later, on July 24, 1969, Apollo 11 landed in the Pacific Ocean.

In July 2007, Armstrong visited Madatech in Haifa and spoke with students from the north of Israel. In response to one of the questions, he said that: “the purpose of the flight to the moon was to expand our knowledge, and indeed, we learned that the human race is not connected to the earth in chains, we can go out and live in other places.”