Heidelberg physicists develop new approach to building signal processing components from individual atoms
In a study on the transport of atoms in ultracold gases, a team of physicists led by Dr. Sandro Wimberger has developed a new approach to how signals might be transmitted at the atomic level.
This could be especially important for realising logic structures with strictly defined functions on the basis of individual atoms, which in turn could find application in transistors or diodes. The research work in the innovative field of atomtronics is being done at the Institute for Theoretical Physics at Heidelberg University.
The researchers are attempting to gain a fundamental understanding of quantum mechanical effects as compared to conventional electronics.
New experimental techniques allow targeted control of ultracold atomic gases – and ergo the bottom-up creation and study of logical components. Dr. Wimberger’s working group is studying the transport of individual atoms through a chain of so-called potential wells. “At an entirely different order of magnitude, imagine an empty egg carton in which the eggs ‘wander’ from one dimple to the next across the entire carton,” explains the Heidelberg physicist.
In these experiments, the atoms behave coherently, meaning they follow the same fixed rule during dynamic transport. In this instance, their behaviour is completely quantum mechanical over the entire chain of potential wells. Dr. Wimberger adds that at the same time, however, different atoms interact with one another, which can affect transport from one well to the next.
The principle is similar to the flow of electrons in a solid state body to which electrical voltage is applied. In this case, the Heidelberg scientists are working with bosonic atoms from a large particle reservoir coupled to a lattice of potential wells. Via the lattice chain, individual bosons flow from the larger into a smaller particle reservoir, generating a particle current in the process.
“The atomic current depends on the properties of the particle reservoir, but especially on the interactions between the atoms,” states Anton Ivanov, the study’s lead author and formerly a member of Dr. Wimberger’s working group. If the interaction is weak, the atomic current flow is directly proportional to the difference in the number of particles between the two reservoirs.
Therefore, it increases linearly with the difference in the number of particles – which is analogous to the voltage in an electrical circuit. If their interaction is strong, the atoms intersperse and block the flow of electricity until it comes to a complete halt.
In their study, the Heidelberg researchers used an analytic approach that was largely confirmed through numerical calculations. The results of their research were published in the “European Physical Journal”.
A. Ivanov, G. Kordas, A. Komnik, S. Wimberger: Bosonic transport through a chain of quantum dots, European Physical Journal B (5 August 2013), doi: 10.1140/epjb/e2013-40417-4
Dr. Sandro Wimberger
Institute for Theoretical Physics
phone: +49 6221 54-5038
Communications and Marketing
phone: +49 6221 542311
Marietta Fuhrmann-Koch | idw - Informationsdienst Wissenschaft
Tracking Down the Causes of Alzheimer’s
03.09.2015 | Universität Basel
Pathways to Deep Decarbonization in Germany
02.09.2015 | Wuppertal Institut für Klima, Umwelt, Energie GmbH
In a survey of NASA's Hubble Space Telescope images of 2,753 young, blue star clusters in the neighboring Andromeda galaxy (M31), astronomers have found that M31 and our own galaxy have a similar percentage of newborn stars based on mass.
By nailing down what percentage of stars have a particular mass within a cluster, or the Initial Mass Function (IMF), scientists can better interpret the light...
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE have developed a highly compact and efficient inverter for use in uninterruptible power...
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from University of Arizona geoscientists. The study is the first to explain how the steep-fronted plateau formed.
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from...
The leaves of the lotus flower, and other natural surfaces that repel water and dirt, have been the model for many types of engineered liquid-repelling surfaces. As slippery as these surfaces are, however, tiny water droplets still stick to them. Now, Penn State researchers have developed nano/micro-textured, highly slippery surfaces able to outperform these naturally inspired coatings, particularly when the water is a vapor or tiny droplets.
Enhancing the mobility of liquid droplets on rough surfaces could improve condensation heat transfer for power-plant heat exchangers, create more efficient...
Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.
"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...
03.09.2015 | Event News
20.08.2015 | Event News
20.08.2015 | Event News
04.09.2015 | Power and Electrical Engineering
04.09.2015 | Machine Engineering
04.09.2015 | Materials Sciences