Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

An Ikerbasque researcher at the University of the Basque Country disentangles the strange behaviour of qubits

25.07.2008
Current technology enables the building of electrical circuits similar to those we use at home but reduced thousands of times in size to a micrometric scale of thousandths of a millimetre.

When these circuits are built of superconductor materials and at near-absolute zero cryogenic temperatures, the world of everyday physics is left behind and the amazing world of quantum physics is entered. In this circuit the behaviour is something like an artificial atom (i.e. like the so-called quantum bits (“qubits”) of quantum computers) and the concepts of quantum optics, quantum information and condensed matter are mixed.

An Ikerbasque researcher, ascribed to the University of the Basque Country (UPV/EHU), Enrique Solano, together with colleagues from Germany and Japan, have been working on an experiment and a theoretical model that show that certain quantum leaps are prohibited at times between levels of a qubit superconductor. This phenomenon is produced on sending photons of light with sufficient energy against a qubit installed within a circuit that simulates the behaviour of microwaves, similar to the ovens commonly used domestically but at a micrometric scale. The research has been published in the prestigious Nature Physics journal under the title, ‘Two-photon probe of the Jaynes-Cummings model and Controlled Symmetry Breaking in Circuit QED’. The article may be consulted on-line and will be included in the next print issue of the journal.

To explain this in an easy way, let us go back to our household circuit where, as with any such circuit, sufficient energy has to be supplied in order to move electrons from one place to another, i.e. the required voltage has to be applied. In an atomic circuit, however, the required energy is supplied through photons of light but this is not sufficient to produce the famous quantum jumps between two atomic energy levels. The additional required factor is the presence of the symmetry of the qubit, an enhancing factor, as it were.

It is as if it were not enough for the quantum nature to have the required energy and it requires, moreover, the presence of the qubit to enable – or otherwise – the quantum leaps stimulated by the photons of light energy. If the qubit presents itself with symmetrical potential, the jump is prohibited and is not produced; curiously, if the potential is asymmetric, the quantum leap is permitted. This strange behaviour has been demonstrated by these researchers both at a theoretical level and in the laboratory, where the rules of prohibition may be activated and deactivated at will.

This research is an important step in the thorough understanding of the quantum jumps permitted and prohibited in superconductor circuits, as well as in the potential application of the electrodynamic quantum of circuits to future technology in quantum computation and information.

Enrique Solano is a PhD in Physics from the Federal University of Río de Janeiro. After working at the Ludwig-Maximilian University in Munich, he has been carrying out his research over the last few months at the UPV/EHU thanks to an agreement between the University and the Ikerbasque Foundation.

Garazi Andonegi | alfa
Further information:
http://www.elhuyar.com
http://www.basqueresearch.com/berria_irakurri.asp?Berri_Kod=1830&hizk=I

More articles from Physics and Astronomy:

nachricht Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun
18.04.2019 | University of Warwick

nachricht In vivo super-resolution photoacoustic computed tomography by localization of single dyed droplets
18.04.2019 | Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences

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: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

Im Focus: A long-distance relationship in femtoseconds

Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.

Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...

Im Focus: Researchers 3D print metamaterials with novel optical properties

Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna

A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

New automated biological-sample analysis systems to accelerate disease detection

18.04.2019 | Life Sciences

Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

18.04.2019 | Physics and Astronomy

New eDNA technology used to quickly assess coral reefs

18.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>