Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Key Ingredient: Change in Material Boosts Prospects of Ultrafast Single-photon Detector

Colorized micrograph of an ultrafast single-photon detector made of superconducting nanowires. NIST researchers use electron beam lithography to pattern the nanowires (vertical lines) on a thin film of tungsten-silicon alloy, which produces more reliable signals than the niobium nitride material used previously.
Credit: Baek/NIST
Colorized micrograph of an ultrafast single-photon detector made of superconducting nanowires. NIST researchers use electron beam lithography to pattern the nanowires (vertical lines) on a thin film of tungsten-silicon alloy, which produces more reliable signals than the niobium nitride material used previously.

Credit: Baek/NIST

Abstract:
By swapping one superconducting material for another, researchers at the National Institute of Standards and Technology (NIST) have found a practical way to boost the efficiency of the world's fastest single-photon detector, while also extending light sensitivity to longer wavelengths. The new tungsten-silicon alloy could make the ultrafast detectors more practical for use in quantum communications and computing systems, experiments testing the nature of reality, and emerging applications such as remote sensing.

Key Ingredient: Change in Material Boosts Prospects of Ultrafast Single-photon Detector

Boulder, CO | Posted on July 2nd, 2011

The detector, made of superconducting nanowires, is one of several sensor designs developed or used at NIST to register individual photons (particles of light). The original nanowire detector, invented in Russia, uses wires made of niobium nitride and has a detection or quantum efficiency—ability to generate an electrical signal for each arriving photon—of less than 10 percent in its simplest, most compact model. NIST's tungsten-silicon alloy version has an efficiency of 19 to 40 percent over a broad wavelength range of 1280 to 1650 nanometers, including bands used in telecommunications.* The limitations are due mainly to imperfect photon absorption, suggesting that, with further design improvements, detector efficiency could approach 100 percent reliably, researchers say.

Superconducting nanowire detectors have many advantages. They are very fast, able to count nearly a billion photons per second, and they operate over a large range of wavelengths, have low dark (false) counts, and produce strong signals, especially at telecom wavelengths. The detectors produce a signal when a photon breaks apart some of the electron pairs that carry current in the superconducting state, where the material has zero resistance. If the nanowires are narrow enough and the DC current across the device is very close to the transition between ordinary and super conductance, a resistive band temporarily forms across each wire, resulting in a measurable voltage pulse.

Niobium nitride is difficult to make into nanowires that are narrow, long, and sensitive enough to work well. NIST researchers selected the tungsten-silicon alloy mainly because it has higher energy sensitivity, resulting in more reliable signals. A photon breaks more electron pairs in the tungsten-silicon alloy than in niobium nitride. The tungsten alloy also has a more uniform and less granular internal structure, making the nanowires more reliably sensitive throughout. As a result of the higher energy sensitivity, tungsten-silicon nanowires can have larger dimensions (150 nanometers wide versus 100 nanometers or less for niobium nitride), which enlarges the detectors' functional areas to more easily capture all photons.

The NIST team now hopes to raise the efficiency of tungsten alloy detectors by embedding them in optical cavities, which trap light for extremely high absorption. High efficiency may enable the use of nanowire detectors in demanding applications such as linear optical quantum computing, which encodes information in single photons. An equally intriguing application may be an experiment to test quantum mechanics—the so-called "loophole-free Bell test." This test of what Einstein called "spooky action at a distance" depends critically on having a nearly 100-percent efficient photon detector. Tungsten-silicon detectors also are sensitive to longer wavelengths of light, in the mid-infrared range, which could be useful for applications such as laser-based remote sensing of trace gases.

* B. Baek, A.E. Lita, V. Verma and S.W. Nam. Superconducting a-WxSi1-x nanowire single-photon detector with saturated internal quantum efficiency from visible to 1850 nm. Applied Physics Letters 98, 251105. Published online June 21, 2011.

####

About National Institute of Standards and Technology (NIST)
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

For more information, please click here

Contacts:
Laura Ost
303-497-4880

Copyright © NIST

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

Non-animal approach to predict impact of nanomaterials on human lung published Archives of Toxicology publishes workshop recommendations May 2nd, 2016

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

New drug-delivery approach holds potential for treating obesity May 2nd, 2016

Spintronics for future information technologies: Spin currents in topological insulators controlled May 2nd, 2016

Laboratories

Exploring phosphorene, a promising new material April 29th, 2016

NREL finds nanotube semiconductors well-suited for PV systems April 27th, 2016

NREL theory establishes a path to high-performance 2-D semiconductor devices April 27th, 2016

Brookhaven's Oleg Gang Named a Battelle 'Inventor of the Year': Recognized for work using DNA to guide and regulate the self-assembly of nanoparticles into clusters and arrays with controllable properties April 25th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

Clay nanotube-biopolymer composite scaffolds for tissue engineering May 1st, 2016

Cooling graphene-based film close to pilot-scale production April 30th, 2016

Personal cooling units on the horizon April 29th, 2016

Quantum Computing

Spintronics for future information technologies: Spin currents in topological insulators controlled May 2nd, 2016

Researchers create a first frequency comb of time-bin entangled qubits: Discovery is a significant step toward multi-channel quantum communication and higher capacity quantum computers April 28th, 2016

Superfast light source made from artificial atom April 28th, 2016

ORIG3N Added to Companies Presenting at Harris & Harris Group's Annual Meeting, Tuesday June 7, 2016, the New York Genome Center April 27th, 2016

Sensors

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

Electrically Conductive Graphene Ink Enables Printing of Biosensors April 23rd, 2016

Highlights from the Graphene Flagship April 22nd, 2016

Team builds first quantum cascade laser on silicon: Eliminates the need for an external light source for mid-infrared silicon photonic devices or photonic circuits April 21st, 2016

Discoveries

Non-animal approach to predict impact of nanomaterials on human lung published Archives of Toxicology publishes workshop recommendations May 2nd, 2016

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

New drug-delivery approach holds potential for treating obesity May 2nd, 2016

Spintronics for future information technologies: Spin currents in topological insulators controlled May 2nd, 2016

Announcements

Non-animal approach to predict impact of nanomaterials on human lung published Archives of Toxicology publishes workshop recommendations May 2nd, 2016

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

New drug-delivery approach holds potential for treating obesity May 2nd, 2016

Spintronics for future information technologies: Spin currents in topological insulators controlled May 2nd, 2016

Tools

Making invisible physics visible: The Jayich Lab has created a new sensor technology that captures nanoscale images with high spatial resolution and sensitivity May 2nd, 2016

Exploring phosphorene, a promising new material April 29th, 2016

JPK reports on the use of a NanoWizard AFM system at the University of Kaiserslautern to study the interaction of bacteria with microstructured surfaces April 28th, 2016

Chemists use DNA to build the world's tiniest thermometer April 27th, 2016

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







Car Brands
Buy website traffic