Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Electron tomography technique leads to 3-D reconstructions at the nanoscale

24.05.2018

A new transmission electron microscopy technique determines three-dimensional position of individual atoms

Understanding the microscopic structure of a material is key to understanding how it functions and its functional properties. Advances in fields like materials science have increasingly pushed abilities to determine these features to even higher resolutions.


This is a schematic of proposed TEM 3-D atomic imaging with multi-slice method with four examples of noisy intensity measurements at different angles of rotation, and 3-D atomic potential reconstructions and 1-D cross-sections along x and y directions.

Credit: David Ren

One technique for imaging at nanoscale resolution, transmission electron microscopy (TEM), is one example of promising technology in this area. Scientists recently found a way to harness the power of TEM to measure the structure of a material at the highest possible resolution - determining the 3D position of every individual atom.

Presenting their work at the OSA Imaging and Applied Optics Congress 25-28 June, in Orlando, Florida, USA, a team of researchers has demonstrated a technique using TEM tomography to determine the 3D positions of strongly scattering atoms.

... more about:
»3D »CT »Electron »OSA »Optical »algorithm »nanoscale »tomography

Through simulation, the group showed that it is possible to reconstruct the atomic potentials with atomic resolution using only image intensity measurements, and that it's possible to do so on molecules that are very sensitive to electron beams.

"Transmission electron microscopy is used extensively in both materials science and biology," said Colin Ophus, National Center for Electron Microscopy, Lawrence Berkeley National Lab, Berkeley, California, and a member of the research team.

"Because we fully solve the nonlinear propagation of the electron beam, our tomographic reconstruction method will enable more quantitative reconstruction of weakly scattering samples, at higher or even atomic resolution."

Similar to the way computerized tomography (CT) scans performed for medical imaging in hospitals are built using a series of two-dimensional cross-sectional images at different increments, electron tomography constructs a three-dimensional volume by rotating samples incrementally, collecting two-dimensional images.

While most CT imaging in hospitals is done with x-rays to determine features of larger things like bones, the beams of electrons used in TEM allows researchers to look with significantly higher resolution, down to the atomic scale.

"However, on the atomic scale we cannot neglect the very complex quantum mechanical effects of the sample on the electron beam," Ophus said. "This means in our work, we must use a much more sophisticated algorithm to recover the atomic structure than those used in an MRI or CT scan."

The TEM setup the group used measured the energy intensity that hits the microscope's sensor, which is proportional to the number of electrons that hit the sensor, a number that depends on how the electron beam is configured for each experiment. Using the intensity data, the new algorithm designed by the group stitched the two-dimensional projected images into a 3D volume.

Making the jump to three dimensions with large fields of view, however, can tax computers exponentially more than dealing with single 2D images. To work around this, they modified their algorithm to be used on graphic processing units (GPUs), which can perform many times more mathematical operations in parallel than typical computer processing units (CPUs).

"We are able to obtain results in a reasonable amount of time for realistic sample dimensions," said David Ren, a member of the team.

With generally weaker bonds between their atoms, biomolecules can be notoriously difficult to study using TEM because the electron beams used to study a metal alloy, for example, would typically tear a biomolecule apart. Lowering the electron dosage in a sample, though, can create images that are so noisy, other algorithms currently in use can't reconstruct a 3D image. Thanks to a more precise physical model, the team's new algorithm has the ability.

Now that they have fully developed the reconstruction algorithm, the team said they hope to apply what they've observed from simulations to experimental data. They plan to make all of their reconstruction codes available as open source for the wider research community.

###

Hear from the research team: MM2D.3. "Tomographic reconstruction of 3D atomic potentials from intensity-only TEM measurements," by the research team from the National Center for Electron Microscopy, Lawrence Berkeley National Lab, Berkeley, California; David Ren; Michael Chen; Colin Ophus; Laura Waller at 11:15 am on 25 June 2018, at the Wyndham Orlando Resort International Drive, Orlando, Florida, United States.

MEDIA REGISTRATION: Media/analyst registration for the OSA Imaging and Applied Optics Conference 2018 can be accessed online. Further information is available on the event website, including travel details.

ABOUT OSA IMAGING AND APPLIED OPTICS CONGRESS

Imaging and Applied Optics Congress provides a comprehensive view of the latest developments in imaging and applied optical sciences, covering the forefront advances in imaging and applied optics as well as the application of these technologies to important industrial, military and medical challenges. The scope of the research presented in ranges from fundamental research to applied. General Chair for the 2018 Congress is Gisele Bennett, Florida Institute of Technology, USA.

Media Contacts:

Rebecca B. Andersen
The Optical Society
+1 202.416.1443
RAndersen@osa.org

Azalea Coste
The Optical Society
+1.202.416.1435
ACoste@osa.org

Media Contact

Rebecca Andersen
randersen@osa.org
202-416-1443

 @opticalsociety

http://www.osa.org 

Rebecca Andersen | EurekAlert!
Further information:
https://www.osa.org/en-us/about_osa/newsroom/news_releases/2018/electron_tomography_technique_leads_to_3d_reconstr/

Further reports about: 3D CT Electron OSA Optical algorithm nanoscale tomography

More articles from Materials Sciences:

nachricht Carbon-loving materials designed to reduce industrial emissions
06.07.2020 | DOE/Oak Ridge National Laboratory

nachricht Thermophones offer new route to radically simplify array design, research shows
03.07.2020 | University of Exeter

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electrons in the fast lane

Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.

Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....

Im Focus: The lightest electromagnetic shielding material in the world

Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.

Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...

Im Focus: Gentle wall contact – the right scenario for a fusion power plant

Quasi-continuous power exhaust developed as a wall-friendly method on ASDEX Upgrade

A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...

Im Focus: ILA Goes Digital – Automation & Production Technology for Adaptable Aircraft Production

Live event – July 1, 2020 - 11:00 to 11:45 (CET)
"Automation in Aerospace Industry @ Fraunhofer IFAM"

The Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM l Stade is presenting its forward-looking R&D portfolio for the first time at...

Im Focus: AI monitoring of laser welding processes - X-ray vision and eavesdropping ensure quality

With an X-ray experiment at the European Synchrotron ESRF in Grenoble (France), Empa researchers were able to demonstrate how well their real-time acoustic monitoring of laser weld seams works. With almost 90 percent reliability, they detected the formation of unwanted pores that impair the quality of weld seams. Thanks to a special evaluation method based on artificial intelligence (AI), the detection process is completed in just 70 milliseconds.

Laser welding is a process suitable for joining metals and thermoplastics. It has become particularly well established in highly automated production, for...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International conference QuApps shows status quo of quantum technology

02.07.2020 | Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

 
Latest News

Coupled hair cells in the inner ear – „Together we are strong!“

06.07.2020 | Health and Medicine

Innovations for sustainability in a post-pandemic future

06.07.2020 | Social Sciences

Carbon-loving materials designed to reduce industrial emissions

06.07.2020 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>