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 Writing and deleting magnets with lasers
19.04.2018 | Helmholtz-Zentrum Dresden-Rossendorf

nachricht Ultrafast electron oscillation and dephasing monitored by attosecond light source
19.04.2018 | Yokohama National University

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: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Scientists re-create brain neurons to study obesity and personalize treatment

20.04.2018 | Health and Medicine

Spider silk key to new bone-fixing composite

20.04.2018 | Materials Sciences

Clear as mud: Desiccation cracks help reveal the shape of water on Mars

20.04.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>