Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Single Photon Detector Conquers the Dark Side

13.08.2003


Researchers from the National Institute of Standards and Technology (NIST) and Boston University have demonstrated a detector that counts single pulses of light, while simultaneously reducing false or “dark counts” to virtually zero.



Reported in the July 28, 2003, issue of Applied Physics Letters*, the advance provides a key technology needed for future development of secure quantum communications and cryptography.

Quantum communications and cryptography is a codemaker’s Holy Grail. The idea is to use a rapid series of light pulses (photons) in one of two different states to transmit information in an unbreakable code.


The photon detector project is part of a multi-disciplinary NIST effort to develop the sophisticated measurement methods needed to make quantum communication and cryptography possible. Funding was provided by the Defense Advanced Research Projects Agency (DARPA) and the NIST Advanced Technology Program (ATP).

Most current photon detectors operate best with visible light, cannot reliably detect single photons and suffer from high dark counts due to random electronic noise. The new device operates with the wavelength of near-infrared light used for fiber optic communications and produces negligible dark counts. Instead of using light-sensitive materials, the NIST device uses a tungsten film coupled to a fiber optic communication line. The film is chilled to 120 milliKelvin, at its transition temperature between normal conductivity and superconductivity. When the fiber optic line delivers a photon to the tungsten film, the temperature rises and the apparatus detects it as an increase in electrical resistance.

The device detects about 20,000 photons per second and works with an efficiency of about 20 percent. With planned improvements, the research team hopes to increase efficiencies to greater than 80 percent.

Media Contact:
Fred McGehan (Boulder), (303) 497-3246

* Miller, A.J., Nam, S.W., Martinis, J.M. and Sergienko, A.V. Demonstration of a low-noise near-infrared photon counter with multi-photon discrimination, Applied Physics Letters (July 28, 2003), Vol. 83, No. 4, pp. 791-793.

Fred McGehan | NIST
Further information:
http://www.nist.gov/public_affairs/techbeat/tb2003_0811.htm#photon

More articles from Physics and Astronomy:

nachricht Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore

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: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>