EGYPTIAN-AMERICAN : Freeze-frame: U of A researchers led by Physicist Prof. Mohammed Hassan develop World’s Fastest Microscope that can see electrons in motion

Imagine owning a camera so powerful it can take freeze-frame photographs of a moving electron – an object traveling so fast it could circle the Earth many times in a matter of a second. Researchers at the University of Arizona have developed the world’s fastest electron microscope that can do just that.

They believe their work will lead to groundbreaking advancements in physics, chemistry, bioengineering, materials sciences and more.

“When you get the latest version of a smartphone, it comes with a better camera,” said Mohammed Hassan, associate professor of physics and optical sciences. “This transmission electron microscope is like a very powerful camera in the latest version of smart phones; it allows us to take pictures of things we were not able to see before – like electrons. With this microscope, we hope the scientific community can understand the quantum physics behind how an electron behaves and how an electron moves.”

Hassan led a team of researchers in the departments of physics and optical sciences that published the research article “Attosecond electron microscopy and diffraction” in the Science Advances journal. Hassan worked alongside Nikolay Golubev, assistant professor of physics; Dandan Hui, co-lead author and former research associate in optics and physics who now works at the Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences; Husain Alqattan, co-lead author, U of A alumnus and assistant professor of physics at Kuwait University; and Mohamed Sennary, a graduate student studying optics and physics.

A transmission electron microscope is a tool used by scientists and researchers to magnify objects up to millions of times their actual size in order to see details too small for a traditional light microscope to detect. Instead of using visible light, a transmission electron microscope directs beams of electrons through whatever sample is being studied. The interaction between the electrons and the sample is captured by lenses and detected by a camera sensor in order to generate detailed images of the sample.

Ultrafast electron microscopes using these principles were first developed in the 2000’s and use a laser to generate pulsed beams of electrons. This technique greatly increases a microscope’s temporal resolution – its ability to measure and observe changes in a sample over time. In these ultrafast microscopes, instead of relying on the speed of a camera’s shutter to dictate image quality, the resolution of a transmission electron microscope is determined by the duration of electron pulses.

The faster the pulse, the better the image.

Ultrafast electron microscopes previously operated by emitting a train of electron pulses at speeds of a few attoseconds. An attosecond is one quintillionth of a second. Pulses at these speeds create a series of images, like frames in a movie – but scientists were still missing the reactions and changes in an electron that takes place in between those frames as it evolves in real time. In order to see an electron frozen in place, U of A researchers, for the first time, generated a single attosecond electron pulse, which is as fast as electrons moves, thereby enhancing the microscope’s temporal resolution, like a high-speed camera capturing movements that would otherwise be invisible.

Hassan and his colleagues based their work on the Nobel Prize-winning accomplishments of Pierre Agostini, Ferenc Krausz and Anne L’Huilliere, who won the Novel Prize in Physics in 2023 after generating the first extreme ultraviolet radiation pulse so short it could be measured in attoseconds.

Using that work as a steppingstone, U of A researchers developed a microscope in which a powerful laser is split and converted into two parts – a very fast electron pulse and two ultra-short light pulses. The first light pulse, known as the pump pulse, feeds energy into a sample and causes electrons to move or undergo other rapid changes. The second light pulse, also called the “optical gating pulse” acts like a gate by creating a brief window of time in which the gated, single attosecond electron pulse is generated. The speed of the gating pulse therefore dictates the resolution of the image. By carefully synchronizing the two pulses, researchers control when the electron pulses probe the sample to observe ultrafast processes at the atomic level.

“The improvement of the temporal resolution inside of electron microscopes has been long anticipated and the focus of many research groups – because we all want to see the electron motion,” Hassan said. “These movements happen in attoseconds. But now, for the first time, we are able to attain attosecond temporal resolution with our electron transmission microscope – and we coined it ‘attomicroscopy.’ For the first time, we can see pieces of the electron in motion.”

source/content: eurekaalert.org / University of Arizona / (headline edited)

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Mohammed Hassan, associate professor of physics and optical sciences, let a group of researchers in developing the first transmission electron microscope powerful enough to capture images of electrons in motion.

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AMERICAN / EGYPTIAN

EGYPT: 79 Cairo University Scholars among Best Scientists in Stanford University report

A total of 79 scientists from Cairo University are among a list of 160,000 scientists whose practical opinions are cited in various specializations with a (2 percent). 

President of Cairo University Dr. Mohamed Othman Elkhosht received a report on Stanford University’s announcement of a list of scientists whose practical opinions are cited in various specializations with a (2 percent), featuring about 160,000 scientists from 149 countries, based on the Scopus database, in 22 scientific specializations, and 176 sub-specialization for distinguished researchers.

Dr. Elkhosht announced that the Stanford list included a large number of Cairo University scientists, with a total of 79 scientists on the two lists, whether the total from 2011 to 2022, or the latest version 2023, as this year’s list included scientists from 11 colleges (an increase of 8% over the previous year).

Number of scholars featured from Cairo University in the report’s 2022 edition was 73 scholars, representing 9 of the university’s faculties, and compared to the number of 74 and 55 scholars during the previous years (2021 and 2020, respectively), Cairo University thus leads all Egyptian universities and research centers in all years from 2020 until now.

Dr. ElKhosht explained that the annual Stanford University report is an objective, external indicator of the progress of scientific research at Cairo University.

It is also a quantitative indicator for the university to identify the number of distinguished faculty members in research and a reflection of the university’s methodology, plan, applied practices, and the support that the university provides to its employees from the various colleges and institutes affiliated with it.

Dr. Mahmoud Al-Saeed, Vice President of the University for Postgraduate Studies and Research, pointed out that the report reflects the strengthening of the confidence of the international scientific and research community in our scientists in all fields and specializations, and that the results of the classification this year included two lists, the first of which is specific to the list of the total practical years 2011 – 2022 (with a total of 417 scientists), While the second included the list of last year, 2022, with a total of 817 scientists, adding that this year’s list (2023 edition) contained 926 Egyptian scientists, while last year’s list (2022 edition) included 680 Egyptian scientists from various universities and research centers, compared to 605 and 396 during the years 2021 and 2020, respectively.

Stanford University used the Scopus database of the international publisher Elsevier to extract various indicators in this list, including global scientific publishing, the number of citations, the H index, and co-authorship, all the way to the composite citation index.

source/content: egypttoday.com (headline edited)

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EGYPT

Essam Heggy – Space and Planetary Scientist at NASA

Dr Essam Heggy . Space and Planetary Scientist.

His main science interests in space and planetary geophysics covers Mars, the Moon, icy satellites and Near Earth Objects.

A member of the several NASA and ESA missions science teams including the MARSIS instrument aboard the Mars Express orbiter (2003-present), the Mini-SAR experiment aboard Chandrayaan-1, the Mini-RF experiment on board the Lunar Reconnaissance Orbiter (2008-present), the CONSERT radar experiment on board the Rosetta mission (2004-2015) and the RIME experiment Onboard JUICE mission for Jupiter Icy Satellites .

Heggy is the Principal Investigator of the NASA Earth Venture Mission Concept OASIS that aims to characterize groundwater in Hyper-Arid Environments .

Heggy served as a panel member for several NASA programs including the Planetary Instrument Definition and Development program, Planetary Geology and Geophysics program, Mars Data Analysis program, Astrobiology program and the Educational and Public Outreach program.

He also edited a special JGR-planets volume on terrestrial and planetary radars. He is on the editing board of Geosciences and National Geography and co-chaired several sessions in American Geophysical Union and other international meetings on planetary radars.

Education:

  • Ph.D – Astronomy and Planetary Science – Paris-Sorbonne University, Paris (2002)

Award/ Honours :

  • JPL/NASA Mariner Award
  • Served as Egyptian President Advisor for Scientific Affairs (2013-2014)

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pix: en.wikipedia.org

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U.S.A / FRANCE / EGYPT / EGYPTIAN AMERICAN / ARAB AMERICAN