Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Efficient and tunable interface for quantum networks

24.05.2012
Quantum computers may someday revolutionize the information world. But in order for quantum computers at distant locations to communicate with one another, they have to be linked together in a network.

While several building blocks for a quantum computer have already been successfully tested in the laboratory, a network requires one additonal component: a reliable interface between computers and information channels. In the current issue of the journal Nature, physicists at the University of Innsbruck report the construction of an efficient and tunable interface for quantum networks.


At the core of the experiment lies an optical resonator consisting of two highly reflective mirrors. Photo: C. Lackner

Quantum technologies promise to redefine the landscape of information processing and communication. We already live in an information age, in which vast amounts of data are sent around the world over optical fibers, but future quantum networks may be many times more powerful. These networks will require interfaces that can transfer information from quantum processors onto light particles (photons).

Such interfaces will allow optical fibers to transmit information-bearing photons between remote data registers, which are likely to be composed of quantum dots or ions. In contrast to classical information, quantum information can’t be copied without being corrupted. Instead, physicists around the world are searching for ways to transfer quantum information between matter and light using entanglement, the quantum property in which the state of one particle depends on the state of a second. Now, a research team led by Rainer Blatt, Tracy Northup, and Andreas Stute at the University of Innsbruck’s Institute for Experimental Physics has demonstrated the first interface between a single ion and a single photon that is both efficient and freely tunable.

High efficiency and precision
The Innsbruck physicists trap a single calcium ion in a so-called Paul trap and place it between two highly reflective mirrors. They excite the ion with a laser, thereby generating a photon which is entangled with the ion and which is reflected back and forth between the mirrors. Custom tuning of the entanglement between ion and photon is possible by adjusting the frequency and amplitude of the laser. This technique has two significant advantages over previous approaches that have entangled atoms with light: “The efficiency with which we produce entangled photons is quite high and in principle could be increased to over 99 percent,” explains Northup. “But above all, what this setup lets us do is generate any possible entangled state.” To this end, the frequency and amplitude of the laser light are carefully chosen so that target collective state of the ion and photon is reached. At the core of the experiment lies an optical resonator consisting of two highly reflective mirrors. Photons bounce back and forth up to 25,000 times between these mirrors, interacting with the ion, before escaping through one mirror into an optical fiber. “Along with an efficient entanglement process, we’ve demonstrated an entangled quantum state between an atom and a photon with the highest precision measured to date,” explains Andreas Stute.
Technology for the future
The experiment offers important insights into the interaction of light and matter and may prove useful in constructing quantum computers or a future quantum internet. “Whenever we have to transfer quantum information from processing sites to communication channels, and vice versa, we’re going to need an interface between light and matter,” explains Northup. The researchers are supported by the Austrian Science Fund and the European Union. Their results appear in the May 24 issue of Nature.
Tunable Ion-Photon Entanglement in an Optical Cavity. A. Stute, B. Casabone, P. Schindler, T. Monz, P. O. Schmidt, B. Brandstätter, T. E. Northup, R. Blatt. Nature 2012.

http://dx.doi.org/10.1038/nature11120

Contact information:

Tracy Northup
Institute for Experimental Physics
University of Innsbruck
Tel.: +43 512 507 6366
E-Mail: Tracy.Northup@uibk.ac.at
Web: http://www.quantumoptics.at/
Christian Flatz
Public Relations Office
University of Innsbruck
Tel.: +43 512 507 32022
Mobil: +43 676 872532022
E-Mail: Christian.Flatz@uibk.ac.at

Dr. Christian Flatz | Universität Innsbruck
Further information:
http://www.quantumoptics.at/
http://www.uibk.ac.at

More articles from Physics and Astronomy:

nachricht Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory

nachricht SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>