Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Detection of single photons via quantum entanglement

As a ‘quantum pendulum’ the ions swing in both directions at the same time. Illustration: IQOQI/Knabl
As a ‘quantum pendulum’ the ions swing in both directions at the same time.

Illustration: IQOQI/Knabl

Abstract:
Almost 200 years ago, Bavarian physicist Joseph von Fraunhofer discovered dark lines in the sun's spectrum. It was later discovered that these spectral lines can be used to infer the chemical composition and temperature of the sun's atmosphere. Today we are able to gain information about diverse objects through light measurements in a similar way. Because often very little light needs to be detected for this, physicists are looking for ever more sensitive spectroscopy methods. In extreme cases, also single particles of light (photons) need to be measured reliably, which is technically challenging.

Detection of single photons via quantum entanglement

Innsbruck, Austria | Posted on July 9th, 2013

Thus, physicists at the Institute for Quantum Optics and Quantum Information (IQOQI) at the Austrian Academy of Sciences and the Institute for Experimental Physics of the University of Innsbruck take a detour via the technique of quantum logic spectroscopy. It was developed some years ago by the group of Nobel laureate David Wineland to build extremely precise atomic clocks. This is one of the first practical applications of quantum information processing and, in the next few years, may lead to a redefinition of the second in the international system of units.

Measurement via entanglement

Christian Roos' and Cornelius Hempel's team of physicists in Innsbruck isolated single ions in an ion trap to study them under controlled conditions. "We do not try to detect the photon that is emitted or absorbed by an ion, but rather the momentum kick the ion receives upon absorption or emission," explains Cornelius Hempel. "While this effect is extremely small, we can detect it by means of quantum physics." The physicists use an additional ‘logic' ion, on which the measurement is performed. "This calcium ion (40Ca+) can be controlled very well in the experiment," says Hempel. As spectroscopy ion the researchers use another isotope of calcium (44Ca+).

In the experiment a laser pulse excites the particles and entangles the electronic state of the logic ion with the vibration of the particles. "In this configuration, also called Schrödinger cat state, the ions swing like a classical pendulum in a trap. But as a ‘quantum pendulum' they swing in both directions at the same time," describes Hempel the central part of the experiment. "We then excite the ion we want to investigate by applying different laser frequencies. At a certain frequency the ion emits a single photon and receives a minimal momentum kick, which causes the vibrational components to be slightly displaced. This can be observed through the electronic state of the logic ion. Combined with this information, the frequency of the laser then allows us to gain information about the internal state of the spectroscopy ion." In the current experiment the scientists detected single photons with a probability of 12 %. "We, thus, prove that this technique works in principal. With a technically optimized set-up we will be able to considerably increase the sensitivity," say Roos and Hempel confidently.

Universal application

"By using the exotic concept of quantum mechanical entanglement we are able to gain practical knowledge about single particles," says Christian Roos excitedly. "Since our method of measurement does not depend that much on the wave length of the detected photon, it may be used for various purposes," adds Cornelius Hempel. For example, energy levels of different atoms and molecules could be investigated by using this technique. Because it is difficult to control molecules in an experiment, this method is an enormous progress for studying more complex structures.

This research, carried out at the Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences and at the Institute for Experimental Physics at Innsbruck University, was supported by the European Union.


Full bibliographic information

Entanglement-enhanced detection of single-photon scattering events. C. Hempel, B. P. Lanyon, P. Jurcevic, R. Gerritsma, R. Blatt, C. F. Roos. Advance online publication. Nature Photonics 2013
DOI: 10.1038/nphoton.2013.172

####

About University of Innsbruck
The University of Innsbruck was founded in 1669 and is one of Austria's oldest universities. Today, with almost 3,500 staff and 23,000 students, it is a place of learning that unifies tradition with future, progress and the joy of discovery. The University of Innsbruck is western Austria's largest institution of higher education and research and serves as major university for the regions of Tyrol, Vorarlberg and South Tyrol and the state of Liechtenstein. At their 15 faculties, scientist are researching and teaching in the various fields of Arts and Letters, Law, Social Sciences and Economics, Catholic Theology, Natural Sciences, Civil Engineering and Architecture.

For more information, please click here

Contacts:
Cornelius Hempel
Institute for Quantum Optics and Quantum Information
Austrian Academy of Sciences
+43 512 507 4722

Copyright © AlphaGalileo

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

News and information

UC research partnership explores how to best harness solar power March 2nd, 2015

Researchers turn unzipped nanotubes into possible alternative for platinum: Aerogel catalyst shows promise for fuel cells March 2nd, 2015

Important step towards quantum computing: Metals at atomic scale March 2nd, 2015

New Hopes for Treatment of Intestine Cancer by Edible Nanodrug March 2nd, 2015

Physics

Moving molecule writes letters: Caging of molecules allows investigation of equilibrium thermodynamics February 27th, 2015

Real-time observation of bond formation by using femtosecond X-ray liquidography February 26th, 2015

Warming up the world of superconductors: Clusters of aluminum metal atoms become superconductive at surprisingly high temperatures February 25th, 2015

Quantum many-body systems on the way back to equilibrium: Advances in experimental and theoretical physics enable a deeper understanding of the dynamics and properties of quantum many-body systems February 25th, 2015

Govt.-Legislation/Regulation/Funding/Policy

Researchers turn unzipped nanotubes into possible alternative for platinum: Aerogel catalyst shows promise for fuel cells March 2nd, 2015

First detailed microscopy evidence of bacteria at the lower size limit of life: Berkeley Lab research provides comprehensive description of ultra-small bacteria February 28th, 2015

Warming up the world of superconductors: Clusters of aluminum metal atoms become superconductive at surprisingly high temperatures February 25th, 2015

SUNY Poly CNSE Researchers and Corporate Partners to Present Forty Papers at Globally Recognized Lithography Conference: SUNY Poly CNSE Research Group Awarded Both ‘Best Research Paper’ and ‘Best Research Poster’ at SPIE Advanced Lithography 2015 forum February 25th, 2015

Discoveries

UC research partnership explores how to best harness solar power March 2nd, 2015

Researchers turn unzipped nanotubes into possible alternative for platinum: Aerogel catalyst shows promise for fuel cells March 2nd, 2015

Important step towards quantum computing: Metals at atomic scale March 2nd, 2015

New Hopes for Treatment of Intestine Cancer by Edible Nanodrug March 2nd, 2015

Announcements

UC research partnership explores how to best harness solar power March 2nd, 2015

Researchers turn unzipped nanotubes into possible alternative for platinum: Aerogel catalyst shows promise for fuel cells March 2nd, 2015

Important step towards quantum computing: Metals at atomic scale March 2nd, 2015

New Hopes for Treatment of Intestine Cancer by Edible Nanodrug March 2nd, 2015

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

Researchers turn unzipped nanotubes into possible alternative for platinum: Aerogel catalyst shows promise for fuel cells March 2nd, 2015

Important step towards quantum computing: Metals at atomic scale March 2nd, 2015

New Hopes for Treatment of Intestine Cancer by Edible Nanodrug March 2nd, 2015

Novel Method to Determine Optical Purity of Drug Components March 1st, 2015

Photonics/Optics/Lasers

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

Leti to Offer Updates on Silicon Photonics Successes at OFC in LA February 27th, 2015

Rice's Stephan Link honored for nanoscience research: The Welch Foundation honors ‘rising star’ with $100,000 Hackerman Award February 26th, 2015

Maximum Precision in 3D Printing: New complete solution makes additive manufacturing standard for microfabrication February 26th, 2015

Quantum nanoscience

Important step towards quantum computing: Metals at atomic scale March 2nd, 2015

Quantum many-body systems on the way back to equilibrium: Advances in experimental and theoretical physics enable a deeper understanding of the dynamics and properties of quantum many-body systems February 25th, 2015

Quantum research past, present and future for discussion at AAAS February 16th, 2015

Exotic states materialize with supercomputers February 12th, 2015

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE