An international investigation involving the participation of the Consejo Superior de Investigaciones Científicas (CSIC) has reproduced the experiment of Thomas Young in a molecule of hydrogen, the smallest molecular system that exists. In 1803 the English scientist tested a pattern of interferences in light from a distant source, on passing through a “double slit” and thus being refracted.
This finding confirmed the theory that light had wave motion properties. The authors of this current research, which appears in the latest issue of the journal Science, uses electrons instead of light and the nuclei of the hydrogen molecule as emitting slits.
CSIC researcher Ricardo Díez, Vicedirector of the Centre for Materials Physics (a mixed body of the CSIC and the University of the Basque Country in Donostia-San Sebastián and co-author of the article, explains their experiment: “These interference patterns are the same as those produced, on a large scale, when sunlight passes through Persian blinds, throwing shadow patterns and, as it were, games, on the walls. This phenomenon is due to the fact that (light) particles, as with electrons, can also have wave motion behaviour”.At much smaller sizes, atomic planes can create interferences in the transmission of X rays, thus providing information about the internal structure of materials. This is the fundamental basis of the experimental techniques such as X ray diffraction, thanks to which the DNA double helix structure was discovered. Ricardo Díez explains, “The Laws that predict, for example, the trajectory of a car at a certain speed are not those that govern the behaviour of atomic-sized particles. On a nanometric scale sizes are measured in units a thousand million times smaller than a metre, and the behaviour of objects at this scale can prove to be surprising, almost magical even!”
The researchers reproduced Young’s experiment in the smallest system existing - a molecule of hydrogen -, which consists of two protons and two electrons. The research team used light generated by the large synchrotron accelerator at the Lawrence Berkeley National Laboratory (USA), to extract the two electrons from the molecule of hydrogen. The two protons carry out the role of the two electron-emitting apertures, separated by an extremely small distance – ten thousand millionths of a metre. On its journey to the detector, where they are collected, each one of the electrons shows an interference pattern that suggests wave nature rather than particle motion, and as if emission had taken place from the two points at the same time.
The interference pattern of each one of the two electrons extracted from the molecule is conditioned by the presence and the velocity of the other: the greater the difference in their speeds, the less the interaction between them and the more visible the interference patterns. Under these conditions, the system is more of a quantum nature. “The analysis of the patterns as a function of velocity enables the investigation of the subtle mechanisms of the transition between classical physics and quantum physics. It is necessary to understand the quantum relationship between a small number of electrons, such as those of hydrogen, as it is the basis of concepts as sophisticated as quantum cryptography or of the future development of quantum computation”, concluded the CSIC researcher.
The study was led by University of Frankfurt researcher Reinhard Dörner and involved, moreover, the participation of German North American and Russian scientists.
Garazi Andonegi | alfa
Astronomers find unexpected, dust-obscured star formation in distant galaxy
24.03.2017 | University of Massachusetts at Amherst
Gravitational wave kicks monster black hole out of galactic core
24.03.2017 | NASA/Goddard Space Flight Center
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy