Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dilating time with superconductors

26.01.2009
Solitary waves trapped in superconducting junctions could illustrate time dilation effects similar to those in special relativity

Solitary waves, known as solitons, can be striking. The first observation of a soliton was documented in 1834: a large moving heap of water formed by a boat on a canal in Scotland. Since then, solitons have been found in many areas of science including nonlinear optics, condensed matter physics, astrophysics (for example Jupiter's red spots), and biology (during energy transfer in DNA).

Solitons can also be found in a so-called Josephson junction, where a thin insulating layer is sandwiched between two superconductors. A team, including RIKEN scientists at the Advanced Science Institute in Wako, has discovered a new type of soliton excitation in a Josephson junction that could be used to measure time dilation effects similar to those in Einstein’s special relativity (1).

In a Josephson junction, the role of a soliton is played by a ‘Josephson vortex’—a lump of magnetic field that can be accelerated inside the material (2). When a Josephson vortex approaches the speed of light for the material, it should start to experience relativistic effects. One of these effects, the Lorentz (length) contraction of solitons, has been observed in experiments. However the measurement of another relativistic effect, time dilation, has been a challenge.

“It has been difficult to observe time dilation for a moving Josephson vortex because we need something internal acting as a clock to measure time in its frame of reference,” explains team member Franco Nori from RIKEN and the University of Michigan, USA. “We can’t find such a clock in conventional Josephson junctions, but we found one that can exist in vortices in long, wide Josephson junctions.”

The ‘clock’ discovered by Nori and co-workers is a nonlinear wave that propagates along Josephson vortices, and therefore belongs to the vortex frame of reference. The excitations are associated with distortions in the Josephson vortices, and are similar to shear waves in solids. They can have almost any shape and retain it for a long time while the wave is propagating.

“The new excitation that we discovered can act as the ‘minute hand’ of a clock, keeping track of time in the frame of reference of a moving soliton,” says team member Dmitry Gulevich from Loughborough University, UK, and RIKEN.

Feo Kusmartsev and Sergey Savel’ev, also from Loughborough University, add: “This effect could be used to transmit information, and as waveguides for Terahertz radiation.” The research team plans to put the predicted effect into practice in the near future.

Reference

1. Gulevich, D.R., Kusmartsev, F.V., Savel’ev, S., Yampol’skii, V.A. & Nori, F. Shape waves in 2D Josephson junctions: Exact solutions and time dilation. Physical Review Letters 101, 127002 (2008).

2. Gulevich, D.R., Savel’ev, S., Yampol'skii, V.A. Kusmartsev, F.V. and Nori, F. Josephson vortices as flexible waveguides for terahertz waves. Journal of Applied Physics 104, 064507 (2008).

The corresponding author for this highlight is based at the RIKEN Digital Materials Team

Saeko Okada | ResearchSEA
Further information:
http://www.rikenresearch.riken.jp/research/630/
http://www.researchsea.com

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

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: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>