Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Optical quantum transistor using single atoms

13.05.2010
Physicists at MPQ control the optical properties of a single atom!

Due to the continued miniaturization of computer chip components, we are about to cross a fundamental boundary where technology can no longer rely on the laws of the macroscopic world. With this in mind, scientists all over the world are researching technologies based on quantum effects that can be used to communicate and process information.

One of the most promising developments in this direction are quantum networks in which single photons communicate the information between different nodes, e.g. single atoms. There the information can be stored and processed. A key element in these systems is Electromagnetically Induced Transparency (EIT), an effect that allows to radically change the optical properties of an atomic medium by means of light.

Previously, scientists have studied this effect and its amazing properties, using atomic ensembles with hundreds of thousands of atoms. Now, scientists in the group of Prof. Gerhard Rempe, Director at the Max Planck Institute of Quantum Optics (MPQ) in Garching and Head of the Quantum Dynamics Division, have managed to control the optical response of a single atom using laser light (Nature, Advanced Online Publication, DOI: 10.1038 /nature09093 May 2010). While representing a corner stone in the development of new quantum based technologies, these results are also fundamental for the understanding of how the quantum behaviour of single atoms can be controlled with light.

Electromagnetically Induced Transparency (EIT) describes the effect, that the interaction of an atomic medium with a weak laser field can be controlled and manipulated coherently with a second, strong laser field. Practically, this is achieved by irradiating the medium with two laser beams: the action of a strong control laser causes the medium to become transparent for a weak probe laser. The properties derived from EIT allow the storing and retrieval of information between an atomic sample and light pulses, thus providing a powerful interface between photonic information and stationary atoms.

In all experiments performed so far, the medium was made of a very large number of atoms. In contrast, in the experiment described here only a single Rubidium atom is addressed. The atom is trapped inside a high-finesse optical cavity in order to amplify the atom-light interaction such that atom and cavity form a strongly coupled system. Then the transmission of laser light – the probe laser – incident on the cavity axis is measured. When there is no atom inside the cavity, the laser light is transmitted. On the other hand, the presence of the atom causes the light to be reflected, and the transmission drops (see Fig. 1a). With an additional control laser of very high intensity applied transverse to the cavity axis, the single-atom EIT condition is achieved and maximum transmission is recovered (See Fig. 1b). The single atom effectively acts as a quantum optical transistor, coherently controlling the transmission of light through the cavity.

In addition, the team of Prof. Rempe succeeded in performing EIT experiments when more atoms were added inside the cavity, one by one in a very controlled way. “Using EIT with a controlled number of atoms provides the possibility to manipulate many quantum properties of light fields transmitted by the cavity”, says Martin Mücke, who works on this experiment as a doctoral student. “Usually photons don’t interact with each other. With this scheme we may be able to achieve a long sought goal: strong interaction between photons, mediated by a single atom. Such a set-up is a potential building block for a working quantum computer.” Olivia Meyer-Streng

Original publication:
Electromagnetically induced transparency with single atoms in a cavity
M. Mücke, E. Figueroa, J. Bochmann, C. Hahn, K. Murr, S. Ritter, C. J. Villas-Boas and G. Rempe.

Nature, Advance Online Publication, DOI: 10.1038/nature09093, May 2010

Contact:
Prof. Dr. Gerhard Rempe
Max Planck Institute of Quantum Optics
Hans-Kopfermann-Straße 1
85748 Garching
Phone: +49 - 89 / 32905 - 701
Fax: +49 - 89 / 32905 – 311
e-mail: gerhard.rempe@mpq.mpg.de
Dr. Eden Figueroa
Max Planck Institute of Quantum Optics
Phone: +49 - 89 / 32905 - 241
e-mail: eden.figueroa@mpq.mpg.de
Dipl. Phys. Martin Mücke
Max Planck Institute of Quantum Optics
Phone: +49 - 89 / 32905 - 356
e-mail: martin.muecke@mpq.mpg.de
Dr. Olivia Meyer-Streng
Press & Public Relations
Max Planck Institute of Quantum Optics
Phone: +49 - 89 / 32905 - 213
e-mail: olivia.meyer-streng@mpq.mpg.de

Dr. Olivia Meyer-Streng | Max-Planck-Institut
Further information:
http://www.mpq.mpg.de

More articles from Physics and Astronomy:

nachricht Prediction: More gas-giants will be found orbiting Sun-like stars
22.02.2017 | Carnegie Institution for Science

nachricht NASA's fermi finds possible dark matter ties in andromeda galaxy
22.02.2017 | NASA/Goddard Space Flight Center

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>