Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Atomic contamination similar to that of gemstones serves as a quantum information carrier

01.10.2018

Impurities in materials are responsible for the colours of gemstones or the performance of modern semiconductors. The same applies to quantum systems, although it has hardly been researched in this field. For the first time, Kaiserslautern researchers were able to implant individual impurities formed by caesium atoms into an ultracold quantum gas of rubidium atoms in a controlled manner. They observed how the impurities exchange quantum mechanical angular momentum (spin) with the gas. They also demonstrated that caesium atoms can store quantum information. This has not been possible so far. The study was published in the renowned journal “Physical Review Letters.”

Individual atomic impurities are also present in other materials, for example in gemstones. They are responsible for various effects in quantum physics and are therefore interesting for experiments. At the TUK, physicists led by Professor Dr. Artur Widera and his doctoral student Felix Schmidt have now observed for the first time how such impurities behave in a Bose-Einstein condensate of rubidium atoms.


The physicists Professor Artur Widera (right) and his doctoral student Felix Schmidt are researching quantum systems.

Koziel/TUK

“In physics, this refers to a state of matter that is comparable with liquid and gaseous states. However, such a condensate is a perfect quantum mechanical state that behaves like a wave,” says Professor Widera, who heads the Individual Quantum Systems group.

For physicists, Bose-Einstein condensates are a popular model for investigating quantum effects - similar to the fruit fly Drosophila which is used in biology and medicine as a model organism to answer genetic questions.

In their current study, the Kaiserslautern physicists have investigated such a contamination in a quantum gas. They cool it down to temperatures close to the absolute zero point of -273.15° Celsius. “In this way, we can control a quantum mechanical system,” says first author Felix Schmidt. The researchers used caesium atoms as an impurity. Five to ten caesium atoms have been immersed in a Bose-Einstein condensate of around 10,000 rubidium atoms.

“The system can be examined under a microscope. The ultracold gas has a size of ten micrometres,” continues the doctoral student. The researchers have thus localized individual impurities and observed the change in their electronic structure, the so-called spin, through interaction with the quantum gas. “So far it has not been possible to observe individual atoms in such a gas. We are pleased that we succeeded in the experiment,” says Schmidt.

The researchers have also investigated whether caesium atoms can be used as information carriers and simultaneously cooled in quantum gas. “For atoms to store information, their electronic state must be preserved,” explains Widera.

“However, since the condensate interacts with the other atoms, there is a risk that they may lose sensitive information as a result of impact.” The researchers have now succeeded for the first time in cooling the impurity atoms in the quantum gas without losing quantum information.

“The model of individual impurities in an ultracold gas realizes a paradigm of quantum physics,” says Professor Widera. “It can serve as a starting point for a variety of other quantum experiments.” In particular, the findings of the Kaiserslautern scientists help to better understand what is happening at the quantum level.

This could play a role in the future, for example, in understanding superconductors and developing new materials. They could transport electricity over long distances without great energy loss at normal ambient temperatures. So far, this has only been possible at temperatures well below freezing point.

The study was published in the renowned journal Physical Review Letters: “Quantum spin dynamics of individual neutral impurities coupled to a Bose-Einstein condensate.” Felix Schmidt, Daniel Mayer, Quentin Bouton, Daniel Adam, Tobias Lausch, Nicolas Spethmann, and Artur Widera. Phys. Rev. Lett. 121, 130403

DOI: 10.1103/PhysRevLett.121.130403

Widera and his doctoral student Felix Schmidt are researching quantum systems. The physicists at the State Research Centre for Optics and Materials Science (OPTIMAS) also work interdisciplinary with working groups from the area of chemistry, mechanical engineering and process engineering as well as electrical engineering and information technology in order to transfer basic research into applications.

Wissenschaftliche Ansprechpartner:

Prof Dr Artur Widera
Department for Individual Quantum Systems
E-mail: widera(at)physik.uni-kl.de
Phone: +49(0)631 205-4130

Felix Schmidt
E-Mail: schmidtf(at)physik.uni-kl.de
Phone: +49(0)631 205-5272

Originalpublikation:

Quantum spin dynamics of individual neutral impurities coupled to a Bose-Einstein condensate. Felix Schmidt, Daniel Mayer, Quentin Bouton, Daniel Adam, Tobias Lausch, Nicolas Spethmann, and Artur Widera. Phys. Rev. Lett. 121, 130403
DOI: 10.1103/PhysRevLett.121.130403

Melanie Löw | Technische Universität Kaiserslautern
Further information:
http://www.uni-kl.de

More articles from Physics and Astronomy:

nachricht Statistical inference to mimic the operating manner of highly-experienced crystallographer
18.09.2019 | Japan Science and Technology Agency

nachricht Scientists create fully electronic 2-dimensional spin transistors
18.09.2019 | University of Groningen

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Happy hour for time-resolved crystallography

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.

The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.

Im Focus: Modular OLED light strips

At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.

Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...

Im Focus: Tomorrow´s coolants of choice

Scientists assess the potential of magnetic-cooling materials

Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....

Im Focus: The working of a molecular string phone

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Potsdam (both in Germany) and the University of Toronto (Canada) have pieced together a detailed time-lapse movie revealing all the major steps during the catalytic cycle of an enzyme. Surprisingly, the communication between the protein units is accomplished via a water-network akin to a string telephone. This communication is aligned with a ‘breathing’ motion, that is the expansion and contraction of the protein.

This time-lapse sequence of structures reveals dynamic motions as a fundamental element in the molecular foundations of biology.

Im Focus: Milestones on the Way to the Nuclear Clock

Two research teams have succeeded simultaneously in measuring the long-sought Thorium nuclear transition, which enables extremely precise nuclear clocks. TU Wien (Vienna) is part of both teams.

If you want to build the most accurate clock in the world, you need something that "ticks" very fast and extremely precise. In an atomic clock, electrons are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

AI for Laser Technology Conference: optimizing the use of lasers with artificial intelligence

29.08.2019 | Event News

 
Latest News

Stroke patients relearning how to walk with peculiar shoe

18.09.2019 | Innovative Products

Statistical inference to mimic the operating manner of highly-experienced crystallographer

18.09.2019 | Physics and Astronomy

Scientists' design discovery doubles conductivity of indium oxide transparent coatings

18.09.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>