Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Diamond-like carbon is formed differently to what was believed -- machine learning enables development of new model

19.04.2018

Customised carbon surfaces can be used in areas such as medical science and water purification.

Researchers at Aalto University and Cambridge University have made a significant breakthrough in computational science by combining atomic-level modelling and machine learning. For the first time, the method has been used to realistically model how an amorphous material is formed at the atomic level: that is, a material that does not have a regular crystalline structure. The approach is expected to have impact on the research of many other materials.


Trajectories followed by incident and knockon atoms during energetic deposition of a tetrahedral amorphous carbon thin film.

Credit: Miguel Caro/Aalto University

'The secret of our success is machine learning, through which we can model the behaviour of thousands of atoms over long periods of time. In this way, we have obtained a more accurate model', explains Postdoctoral Researcher Miguel Caro.

The team's simulations reveal that diamond-like carbon film is formed at the atomic level in a different way than was thought. The prevailing understanding over the last 30 years of the formation mechanism for amorphous carbon film has been based on assumptions and indirect experimental results. Neither a good nor even an adequate atomic-level model has been available up to now. The new method has now overturned the earlier qualitative models and provided a precise atomic-level picture of the formation mechanism.

'Earlier, amorphous carbon films were thought to form when atoms are packed together in a small area. We have demonstrated that mechanical shock waves can cause the formation of diamond-like atoms further away from the point at which the impacting atoms hit the target, reports Caro, who performed the simulations on CSC (IT Center for science) supercomputers, modelling the deposition of tens of thousands of atoms.

Results open up significant new avenues for research

There are countless different uses for amorphous carbon. It is used as a coating in many mechanical applications, such as car motors, for example. In addition, the material can also be used for medical purposes and in various energy-related, biological and environmental applications.

'For us, the most important application is biosensors. We have used very thin amorphous carbon coatings for identifying different biomolecules. In these applications, it is especially important to know the films' electrical, chemical and electrochemical properties and to be able to customise the material for a particular application', explains Professor Tomi Laurila.

Dr Volker Deringer, a Leverhulme Early Career Fellow, is particularly excited about using these methods for amorphous materials.

'Teaming up has been a great success', conclude Deringer and Caro, who are continuing the collaboration between their institutions through ongoing visits. The team expect that their approach will help many others in experimental materials research, because it can give information about materials with a level of precision close to that of quantum mechanical methods, but simultaneously can make use of thousands of atoms and long simulation times. Both of these are extremely important for a realistic picture of the processes in experiments.

'I'm especially excited about the kinds of opportunities this method offers for further research. This atomic-level model produces verifiably correct results that correspond exceptionally well to the experimental results, revealing also for the first time the atomic-level phenomena behind the results. Using the model, we can, for example, predict what kind of carbon surface would be best for measuring neurotransmitters dopamine and serotonin', says Laurila.

###

The research has been published in Physical Review Letters:
Miguel A. Caro, Volker L. Deringer, Jari Koskinen, Tomi Laurila, and Gábor Csányi
Growth Mechanism and Origin of High sp3 Content in Tetrahedral Amorphous Carbon
Phys. Rev. Lett. 120, 166101 (2018)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.166101

Further information:
Miguel Caro
Postdoctoral Researcher
Aalto University
miguel.caro@aalto.fi
+ 358504079988

Tomi Laurila
Professor
Aalto University
tomi.laurila@aalto.fi
+358503414375

Dr Volker Deringer
Leverhulme Early Career Fellow
University of Cambridge
vld24@cam.ac.uk
+44 7494 989967

Media Contact

Miguel Caro
miguel.caro@aalto.fi
358-504-079-988

 @aaltouniversity

http://www.aalto.fi/en/ 

Miguel Caro | EurekAlert!

Further reports about: amorphous materials atomic level crystalline structure

More articles from Materials Sciences:

nachricht Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern
20.07.2018 | Princeton University

nachricht Relax, just break it
20.07.2018 | DOE/Argonne National Laboratory

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>