Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

World record: Quantum teleportation over 143 kilometres

06.09.2012
Physicists from the group of Prof. Anton Zeilinger at the Institute of Quantum Optics and Quantum Information (IQOQI) and the University of Vienna have set a new world record for distance in quantum teleportation.
The team succeeded in teleporting the quantum state of a particle of light over a separation of 143 kilometres from the Canary Island La Palma to Tenerife. The experiment got theoretical support from Dr. Johannes Kofler from the group of Prof. Ignacio Cirac at the Max Planck Institute of Quantum Optics (MPQ). The results are published this week in Nature.

The so-called "quantum internet" is a future vision for information processing. It is not based anymore on classical computer networks but on the current developments of modern quantum information, where individual quantum particles are the carriers of information. Quantum networks promise absolutely secure communication and enhanced computation power for decentralised tasks compared to any conceivable classical technology. Due to the transmission losses in conventional glass fibres a global quantum network will likely base on the free-space transfer of quantum states, e.g., between satellites and from satellites to ground. The now realized quantum teleportation over a distance of 143 kilometres, beating a just a few months old Chinese record of 97 kilometres, is a significant step towards this future technology.

On the island of La Palma the team of physicists produced entangled pairs of particles of light (photons 2 and 3, see figure). Quantum entanglement means that none of the photons taken by itself has a definite polarisation but that, if one measures the polarisation of one of the photons and obtains a random result, the other photon will always show a perfectly correlated polarisation. This type of quantum correlation cannot be described by classical physics and Albert Einstein therefore called it "spooky action at a distance". Photon 3 was then sent through the air to Tenerife, across the Atlantic Ocean at an altitude of about 2400 metres and over a distance of 143 kilometres, where it was caught by a telescope of the European Space Agency.
Photon 2 remained in the laboratory at La Palma. There, the experimenters created additional particles of light (photon 1 in the figure) in a freely selectable polarization state which they wanted to teleport. This was achieved in several steps: First, a special kind of joint measurement, the so-called Bell measurement ("BM"), was performed on photons 1 and 2, which irrevocably destroys both photons. Two possible outcomes of this measurement were discriminated, and the corresponding classical information was sent via a conventional laser pulse (violet in the figure) to Tenerife. There, depending on which of the outcomes of the Bell measurement had been received, the polarization of photon 3 was either rotated by 90 degrees or left completely unchanged. This transformation ("T") completed the teleportation process, and the polarization of photon 3 on Tenerife was now identical with the initial polarization of photon 1 on La Palma.

The complexity of the setup and the environmental conditions (changes of temperature, sand storms, fog, rain, snow) constituted a significant challenge for the experiment. They also demanded a combination of modern quantum optical technologies concerning the source of entangled particles of light, the measurement devices, and the temporal synchronization of the two laboratories. The experiment therefore represents a milestone, which demonstrates the maturity and applicability of these technologies for future global quantum networks. For the next step of satellite-based quantum teleportation an international collaboration of the Austrian and Chinese Academy of Sciences plans to shoot a satellite into space in the foreseeable future.

Picture download:
https://dl.dropbox.com/u/5536900/Nature/startrails-1.jpg (Copyright: IQOQI Vienna)
https://dl.dropbox.com/u/5536900/Nature/startrails-2.jpg (Copyright: IQOQI Vienna)

Original publication:
Xiao-song Ma, Thomas Herbst, Thomas Scheidl, Daqing Wang, Sebastian Kropatschek, William Naylor, Bernhard Wittmann, Alexandra Mech, Johannes Kofler, Elena Anisimova, Vadim Makarov, Thomas Jennewein, Rupert Ursin, Anton Zeilinger
Quantum teleportation over 143 kilometres using active feed-forward
Nature, 5 September 2012, Advance Online Publication, DOI:10.1038/nature11472

Contact:
Dr. Johannes Kofler
Max Planck Institute of Quantum Optics (MPQ)
Hans-Kopfermann-Straße 1
85748 Garching
Tel.: +49 89 32905 242
E-Mail: johannes.kofler@mpq.mpg.de

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

More articles from Physics and Astronomy:

nachricht Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics

nachricht What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin

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: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>