Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NIST Detector Counts Photons With 99 Percent Efficiency

16.04.2010
Scientists at the National Institute of Standards and Technology (NIST) have developed* the world’s most efficient single photon detector, which is able to count individual particles of light traveling through fiber optic cables with roughly 99 percent efficiency. The team’s efforts could bring improvements to secure electronic communication, advanced quantum computation and the measurement of optical power.

Using essentially the same technology that permitted them to achieve 88 percent detection efficiency five years ago,** the team has enhanced its ability to detect photons largely by improving the alignment of the detector and the optical fibers that guide photons into it.

The basic principle of the detector is to use a superconductor as an ultra-sensitive thermometer. Each individual photon hitting the detector raises the temperature—and increases electrical resistance—by a minute amount, which the instrument registers as the presence of a photon.

According to team member Sae Woo Nam, the advantage of this type of single photon detector is that the new detector design not only measures lower levels of light than have ever been possible, but does so with great accuracy.

“When these detectors indicate they’ve spotted a photon, they’re trustworthy. They don’t give false positives,” says Nam, a physicist with NIST’s Optoelectronics division. “Other types of detectors have really high gain so they can measure a single photon, but their noise levels are such that occasionally a noise glitch is mistakenly identified as a photon. This causes an error in the measurement. Reducing these errors is really important for those who are doing calculations or communications.”

The ability to count individual photons is valuable to designers of certain types of quantum computers as well as scientists engaged in quantum optical experiments, which concern exotic states of light that cannot be described by classical physics. But one of the most promising potential applications of a high-efficiency photon detector is a way to secure long-distance data transmission against unwanted interception. A detector that could recognize that a photon forming part of a transmission was missing would be a substantial defense against information theft.

The team has optimized the detection for 810 nanometers—an infrared wavelength—and it still has high efficiency at other wavelengths that are interesting for fiber optic communications, as well as the quantum optics community. Ironically, the detector is so efficient that it outstrips current technology’s ability to determine its precise efficiency.

“We can’t be sure from direct measurement that we’ve achieved 99 percent efficiency because the metrology is not in place to determine how close we are—there’s no well-established technique,” Nam says. “What is great about our latest progress is that we measure nearly the same detection efficiency for every device we build, package and test. It’s the reproducibility that gives us confidence.”

The team is currently working to develop evaluation techniques that can measure up to the detector’s abilities, and Nam says the team’s creation could also help evaluate other light-gathering devices.

“NIST offers a standardized service for measuring the efficiency of photodetectors and optical power meters,” he says. “We’re trying to develop a calibration technique that extends to ultra-low levels of light. It should be valuable for anyone looking at single photons.”

* A.E. Lita, B. Calkins, L.A. Pellouchoud, A.J. Miller and S. Nam. Superconducting transition-edge sensors optimized for high-efficiency photon-number resolving detectors. Presented at the SPIE Symposium on SPIE Defense, Security, and Sensing, Orlando World Center Marriott Resort and Convention Center, Crystal J1 Ballroom, 3 p.m. April 7, 2010.

** See “NIST Photon Detectors Have Record Efficiency” in NIST Tech Beat, June 2, 2005, at www.nist.gov/public_affairs/techbeat/tb2005_0602.htm#photon.

Chad Boutin | Newswise Science News
Further information:
http://www.nist.gov

Further reports about: NIST Photon SPIE energy efficiency quantum computer single photon

More articles from Physics and Astronomy:

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

nachricht Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz

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: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>