A research team headed by Prof. Dr. Frank Stienkemeier and Dr. Lukas Bruder of the University of Freiburg's Institute of Physics has succeeded for the first time in applying 2D-spectroscopy to isolated molecular systems and thus in tracing the interactive processes at a molecular level more precisely. The team has published its results in the science journal "Nature Communications".
Behind every natural process are processes at atomic and molecular levels. These often take place on very short time scales, often they are faster than a billionth of a second and are based on the interplay of many factors.
Until now this has made it difficult to unencrypt the precise microscopic mechanisms such as the conversion of energy in photovoltaics or photosynthesis.
In this area of research coherent two-dimensional spectroscopy has been established, which involves ultra-short laser pulses being shot at the matter. This method has enabled researchers to follow the dynamics of corresponding processes, once the matter has absorbed the light.
Two-dimensional spectroscopy provides a far greater amount of information than other methods, combined with a high time resolution in the range of femtoseconds - a femtosecond is the millionth part of a billionth of a second. However, for technical reasons, this method had until now been restricted to studying bulk liquid or solid material.
"In previous experiments the samples were very complex, which made it extremely difficult to isolate individual quantum-mechanical effects and study them precisely. Our approach overcomes this hurdle," explains Bruder, who headed the experiment.
In preparation for the experiment, the scientists produced superfluid helium droplets, which have no friction, in an ultrahigh vacuum.
The droplets are only a few nanometers in size and serve as a substrate in which the researchers synthesize the actual molecular structures using a modular principle, in other words by combining molecular components one by one. These structures are then studied by means of 2D-spectroscopy.
"In the experiments we combined various specific technologies which drastically improved the measurement sensitivity of the 2D-spectroscopy. Only by doing this was it possible for us to study isolated molecules," explains Bruder.
In an initial study, the Freiburg scientists produced extremely cold molecules of the chemical element Rubidium in an unusual quantum state, whereby the atoms of the molecule are only weakly bonded, and analyzed their light-induced reactions under the influence of the helium environment.
"Our approach opens up a range of applications, specifically in the field of photovoltaics or optoelectronics, and will eventually contribute to a better understanding of fundamental processes," says Stienkemeier.
The 2D-spectroscopy research project was funded as part of the International Graduate School "CoCo", which was established by the German Research Foundation, and the "COCONIS" project of the European Research Council (ERC).
L. Bruder, U. Bangert, M. Binz, D. Uhl, R. Vexiau, N. Bouloufa-Maafa, O. Dulieu, and F. Stienkemeier: Coherent multidimensional spectroscopy of dilute gas-phase nanosystems. Nature Communications 9, 4823 (2018). DOI: 10.1038/s41467-018-07292-w
Institute of Physics
University of Freiburg
Dr. Frank Stienkemeier | EurekAlert!
ATLAS telescope discovers first-of-its-kind asteroid
25.05.2020 | University of Hawaii at Manoa
New gravitational-wave model can bring neutron stars into even sharper focus
22.05.2020 | University of Birmingham
Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.
When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...
Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.
Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...
Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.
A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...
By studying the chemical elements on Mars today -- including carbon and oxygen -- scientists can work backwards to piece together the history of a planet that once had the conditions necessary to support life.
Weaving this story, element by element, from roughly 140 million miles (225 million kilometers) away is a painstaking process. But scientists aren't the type...
Study co-led by Berkeley Lab reveals how wavelike plasmons could power up a new class of sensing and photochemical technologies at the nanoscale
Wavelike, collective oscillations of electrons known as "plasmons" are very important for determining the optical and electronic properties of metals.
19.05.2020 | Event News
07.04.2020 | Event News
06.04.2020 | Event News
25.05.2020 | Medical Engineering
25.05.2020 | Information Technology
25.05.2020 | Information Technology