Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'Cavity protection effect' helps to conserve quantum information

18.08.2014

Coupling atomic spins in diamonds to microwave resonators could lead to new quantum technologies. Researchers at the Vienna University of Technology (TU Wien) have now managed to dramatically prolong the time these systems can store information

The electronics we use for our computers only knows two different states: zero or one. Quantum systems on the other hand can be in different states at once, they can store a superposition of "zero" and "one".

Diamond Chip

The quantum system studied at TU Wien (Vienna): a black diamond (center) contains nitrogen atoms, which are coupled to a microwave resonator.

Credit: TU Wien

This phenomenon could be used to build ultrafast quantum computers, but there are several technological obstacles that have to be overcome first. The biggest problem is that quantum states are quickly destroyed due to interactions with the environment. At TU Wien (Vienna), scientists have now succeeded in using a protection effect to enhance the stability of a particularly promising quantum system.

A Quantum Computer Made of Two Systems

There are various concepts for possible quantum computers. "What we use is a hybrid system of two completely different quantum technologies", says Johannes Majer. Together with his team, he couples microwaves and atoms, investigating and building a new type of quantum memory.

The theorists Dmitry Krimer and Stefan Rotter developed a theoretical model describing the complex dynamics in such hybrid quantum systems.

In a microwave resonator, photons are created. They interact with the spin of nitrogen atoms, which are built into a diamond. The microwave resonator can be used to quickly transport quantum information.

The atomic spins in the diamond can store it – at least for a period of several hundred nanoseconds, which is long compared to the time scale on which photons move in the microwave resonator.

"All nitrogen atoms are completely identical. But when they are placed in slightly different surroundings, they have slightly different transition frequencies", says Stefan Putz, PhD-student at Vienna University of Technology. The atomic spins behave like a room full of pendulum clocks. Initially they may oscillate in sync, but as they can never be precisely identical, they eventually lose their rhythm, creating random noise.

Coupling Causes Order

"By creating a strong coupling between the atomic spins and the resonator, it is possible to dramatically prolong the time during which the spins oscillate in strict time – if their energy levels obey the right distribution", says Dmitry Krimer. The atomic spins do not directly interact with each other, but the mere fact that they are collectively coupled to the microwave resonator prevents them from changing into a state in which they cannot be used for processing quantum information any longer. This protection effect considerably enhances the duration in which quantum information can be read out from the atomic spins.

"Improving the quantum coherence time with this cavity protection effect opens up many promising applications for our hybrid quantum system", says Johannes Majer. The paper has now been published in Nature Physics.

Further information
Dr. Johannes Majer
Institute for Atomic and Subatomic Physics
TU Wien
Stadionallee 2, 1020 Wien
T: +43-1-58801-141838
johannes.majer@tuwien.ac.at

Florian Aigner | Eurek Alert!
Further information:
http://www.tuwien.ac.at

Further reports about: Cavity Coupling Physics Quantum Technology interact nitrogen oscillate photons technologies

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 >>>