Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > A glass fiber that brings light to a standstill: By coupling photons to atoms, light in a glass fiber can be slowed down to the speed of an express train; for a short while it can even be brought to a complete stop

Atoms coupled to a glass fiber: A system that can slow down light dramatically.
CREDIT: TU Wien
Atoms coupled to a glass fiber: A system that can slow down light dramatically.

CREDIT: TU Wien

Abstract:
Light is an extremely useful tool for quantum communication, but it has one major disadvantage: it usually travels at the speed of light and cannot be kept in place. A team of scientists at the Vienna University of Technology has now demonstrated that this problem can be solved - not only in strange, unusual quantum systems, but in the glass fiber networks we are already using today.

A glass fiber that brings light to a standstill: By coupling photons to atoms, light in a glass fiber can be slowed down to the speed of an express train; for a short while it can even be brought to a complete stop

Vienna, Austria | Posted on April 9th, 2015

By coupling atoms to glass fibers light was slowed down to a speed of 180 km/h. The team even managed to bring the light to a complete stop and to retrieve it again later. This technology is an important prerequisite for a future glassfiber-based quantum-internet, in which quantum information can be teleported over great distances.

Light Pulses, Slower than an Express Train

In a vacuum, the speed of light is always the same - approximately 300 million meters per second. When light is sent through a medium such as glass or water, it is slowed down a little bit due to its interaction with the material. "In our system, this effect is extreme, because we are creating an exceedingly strong interaction between light and matter", says Professor Arno Rauschenbeutel (TU Wien / Vienna Center for Quantum Science and Technology). "The speed of light in our glass fiber is only 180 kilometers per hour. Any express train can top that."

Quantum Communication in Existing Fiber Networks

"There are different ways of quantum mechanically transferring information", says Clément Sayrin. "Glass fiber technology is a particularly attractive option - after all, a worldwide glass fiber net already exists, and we are already using it to transmit data."

At the TU Wien, cesium atoms are coupled to an ultrathin glass fiber. When the atom absorbs laser light it can pass from a state of low energy to a state of higher energy - provided that the energy of the absorbed photon matches the energy difference between the two states. This light, however, cannot be retrieved in a controlled way.

That is why the Viennese team used an additional control-laser in their experiment, which couples the high-energy state to a third atomic state. "The interplay between these three quantum states prevents the photon from just being absorbed and randomly emitted. Instead, the photon's quantum information is transferred to an ensemble of atoms in a controlled way, and it can be stored there for some time." The photon is turned into a collective excitation of atoms.

After two microseconds, a period of time in which the light would normally have travelled about half a kilometre, the control laser was used to prompt the atoms to emit the light back into the glass fiber. The properties of the photon stay exactly the same - an important prerequisite for quantum communication.

Being able to store photons is an important technological step towards quantum communication over great distances. "Quantum physics allows us to create a connection between sender and receiver, which makes eavesdropping impossible", says Arno Rauschenbeutel. "The fundamental laws of quantum physics make sure that no one can tap the connection without being noticed."

####

For more information, please click here

Contacts:
Florian Aigner

43-158-801-41027

Further information:

Dr. Christoph Clausen
Institute for Atomic and Subatomic Physics
Vienna Center for Quantum Science and Technology
TU Wien
Stadionallee 2, 1020 Wien
+43-1-58801-141713


Prof. Arno Rauschenbeutel
Institute for Atomic and Subatomic Physics
Vienna Center for Quantum Science and Technology
TU Wien
Stadionallee 2, 1020 Wien
T: +43-1-58801-141761

Copyright © Vienna University of Technology

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Physics

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

News and information

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

Wireless/telecommunications/RF/Antennas/Microwaves

HKUST researchers develop new integration technique for efficient coupling of III-V and silicon February 16th, 2024

Optical-fiber based single-photon light source at room temperature for next-generation quantum processing: Ytterbium-doped optical fibers are expected to pave the way for cost-effective quantum technologies November 3rd, 2023

Chip-based dispersion compensation for faster fibre internet: SUTD scientists developed a novel CMOS-compatible, slow-light-based transmission grating device for the dispersion compensation of high-speed data, significantly lowering data transmission errors and paving the way for June 30th, 2023

Researchers demonstrate co-propagation of quantum and classical signals: Study shows that quantum encryption can be implemented in existing fiber networks January 20th, 2023

Possible Futures

Ben-Gurion University of the Negev researchers several steps closer to harnessing patient's own T-cells to fight off cancer June 6th, 2025

Researchers unveil a groundbreaking clay-based solution to capture carbon dioxide and combat climate change June 6th, 2025

Cambridge chemists discover simple way to build bigger molecules – one carbon at a time June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Discoveries

Researchers unveil a groundbreaking clay-based solution to capture carbon dioxide and combat climate change June 6th, 2025

Cambridge chemists discover simple way to build bigger molecules – one carbon at a time June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Announcements

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Cambridge chemists discover simple way to build bigger molecules – one carbon at a time June 6th, 2025

Electrifying results shed light on graphene foam as a potential material for lab grown cartilage June 6th, 2025

Quantum computers simulate fundamental physics: shedding light on the building blocks of nature June 6th, 2025

A 1960s idea inspires NBI researchers to study hitherto inaccessible quantum states June 6th, 2025

Photonics/Optics/Lasers

INRS and ELI deepen strategic partnership to train the next generation in laser science:PhD students will benefit from international mobility and privileged access to cutting-edge infrastructure June 6th, 2025

Institute for Nanoscience hosts annual proposal planning meeting May 16th, 2025

Following the folds – with quantum technology: The connection between a crumpled sheet of paper and quantum technology: A research team at the EPFL in Lausanne (Switzerland) and the University of Konstanz (Germany) uses topology in microwave photonics to make improved systems of May 16th, 2025

Programmable electron-induced color router array May 14th, 2025

Quantum nanoscience

A new study provides insights into cleaning up noise in quantum entanglement:When it comes to purifying quantum entanglement, new theoretical work highlights the importance of tailoring noise-minimizing solutions to specific quantum systems May 16th, 2025

Superconductors: Amazingly orderly disorder: A surprising effect was discovered through a collaborative effort by researchers from TU Wien and institutions in Croatia, France, Poland, Singapore, Switzerland, and the US during the investigation of a special material: the atoms are May 14th, 2025

Programmable electron-induced color router array May 14th, 2025

Unraveling the origin of extremely bright quantum emitters: Researchers from Osaka University have discovered the fundamental properties of single-photon emitters at an oxide/semiconductor interface, which could be crucial for scalable quantum technology February 28th, 2025

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project