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
Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun
18.04.2019 | University of Warwick
In vivo super-resolution photoacoustic computed tomography by localization of single dyed droplets
18.04.2019 | Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.
Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...
The technology could revolutionize how information travels through data centers and artificial intelligence networks
Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...
Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.
Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...
Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna
A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
18.04.2019 | Life Sciences
18.04.2019 | Physics and Astronomy
18.04.2019 | Life Sciences