Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Highly stable quantum light source for applications in quantum information developped

04.11.2013
Physicists at the University of Basel have been successful in generating photons - the quantum particles of light – with only one color. This is useful for quantum information.

The scientists have actively stabilized the wavelength of the photons emitted by a semiconductor thereby neutralizing the charge noise in the semiconductor. The results were developed in close collaboration with the Universities of Bochum, Paderborn and Lyon and have been published in the magazine «Physical Review X».

Light consists of quantum particles, so-called photons. With a single photon it is possible to transfer quantum information. The information can be encoded in the polarization or in the phase of the photons’ wave packets and can be used in quantum communication and computation. In such applications, a single-photon source, a device that emits photons one by one, is a prerequisite. One of the most promising platforms for single-photon sources is based on semiconductor quantum dots. One major unsolved problem is, however, that the “color” (or wavelength) of the photons emitted by a quantum dot is not locked to a precise value; rather, it wanders around randomly.

The fluctuations in the wavelength of the photons originate from imperfections in the vicinity of the quantum dot. These imperfections can trap electric charge in the semiconductor resulting in noise. To remove this «charge noise», Prof. Warburton of the Department of Physics at the University of Basel and his team have developed a quantum-classical hybrid system that connects a single quantum dot to a constant-wavelength laser. This stabilizing mechanism monitors continuously the fluctuations via the highly sensitive optical absorption of the quantum dot. By applying the exact opposite effect, the electrical field experienced by the quantum dot can be actively regulated.

Stream of single-color photons
With this system, the scientists succeeded in generating a nearly perfect stream of single-color photons. A notable point is that a quantum system could be made technically useful by using a classical feedback scheme, a general feature which has not been demonstrated up until now.

This new scheme - through its highly effective removal of the charge noise - potentially enables a stable single-photon source and may lead, for example, to improvement in semiconductor-based spin quibts. The study was supported by the National Center of Competence in Research «QSIT – Quantum Science and Technology», for which the University of Basel acts as Co-Leading-House.

Original Citation
Jonathan H. Prechtel, Andreas V. Kuhlmann, Julien Houel, Lukas Greuter, Arne Ludwig, Dirk Reuter, Andreas D. Wieck, and Richard J. Warburton
Frequency-Stabilized Source of Single Photons from a Solid-State Qubit
Phys. Rev. X 3, 041006 (2013) | DOI: 10.1103/PhysRevX.3.041006
Weitere Informationen:
http://www.unibas.ch/index.cfm?uuid=13E5EDEA0A1F08911EC9FDCCE058ED96
&type=search&show_long=1&&o_lang_id=2

Reto Caluori | Universität Basel
Further information:
http://www.unibas.ch

More articles from Physics and Astronomy:

nachricht Astronomers find unexpected, dust-obscured star formation in distant galaxy
24.03.2017 | University of Massachusetts at Amherst

nachricht Gravitational wave kicks monster black hole out of galactic core
24.03.2017 | NASA/Goddard Space Flight Center

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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>