Navigation Links
Extreme darkness: Carbon nanotube forest covers NIST's ultra-dark detector
Date:8/18/2010

Harnessing darkness for practical use, researchers at the National Institute of Standards and Technology (NIST) have developed a laser power detector coated with the world's darkest material‑a forest of carbon nanotubes that reflects almost no light across the visible and part of the infrared spectrum.

NIST will use the new ultra-dark detector, described in a new paper in Nano Letters,* to make precision laser power measurements for advanced technologies such as optical communications, laser-based manufacturing, solar energy conversion, and industrial and satellite-borne sensors.

Inspired by a 2008 paper by Rensselaer Polytechnic Institute (RPI) on "the darkest man-made material ever,"** the NIST team used a sparse array of fine nanotubes as a coating for a thermal detector, a device used to measure laser power. A co-author at Stony Brook University in New York grew the nanotube coating. The coating absorbs laser light and converts it to heat, which is registered in pyroelectric material (lithium tantalate in this case). The rise in temperature generates a current, which is measured to determine the power of the laser. The blacker the coating, the more efficiently it absorbs light instead of reflecting it, and the more accurate the measurements.

The new NIST detector uniformly reflects less than 0.1 percent of light at wavelengths from deep violet at 400 nanometers (nm) to near infrared at 4 micrometers (μm) and less than 1 percent of light in the infrared spectrum from 4 to 14 μm. The results are similar to those reported for the RPI material and in a 2009 paper by a Japanese group. The NIST work is unique in that the nanotubes were grown on pyroelectric material, whereas the other groups grew them on silicon. NIST researchers plan to extend the calibrated operating range of their device to 50 or even 100 micrometer wavelengths, to perhaps provide a standard for terahertz radiation power.

NIST previously made detector coatings from a variety of materials, including flat nanotube mats. The new coating is a vertical forest of multiwalled nanotubes, each less than 10 nanometers in diameter and about 160 micrometers long. The deep hollows may help trap light, and the random pattern diffuses any reflected light in various directions. Measuring how much light was reflected across a broad spectrum was technically demanding; the NIST team spent hundreds of hours using five different methods to measure the vanishingly low reflectance with adequate precision. Three of the five methods involved comparisons of the nanotube-coated detector to a calibrated standard.

Carbon nanotubes offer ideal properties for thermal detector coatings, in part because they are efficient heat conductors. Nickel phosphorous, for example, reflects less light at some wavelengths, but does not conduct heat as well. The new carbon nanotube materials also are darker than NIST's various Standard Reference Materials for black color developed years ago to calibrate instruments.


'/>"/>

Contact: Laura Ost
laura.ost@nist.gov
303-497-4880
National Institute of Standards and Technology (NIST)
Source:Eurekalert  

Related biology technology :

1. Famed IT Investor and Director of 23andme Esther Dyson Identifies on IdeasProject.com Genetic Information as an Extremely Disruptive Force
2. Using carbon nanotubes in lithium batteries can dramatically improve energy capacity
3. Elekta / Mitsubishi Electric Collaboration Helps Japans Gunma University Heavy Ion Medical Center Launch Advanced Carbon Ion Therapy for Treating Cancer
4. From pollutant to profit -- nanoscience turns carbon on its head
5. Scientists discover how ocean bacterium turns carbon into fuel
6. Extra large carbon
7. InfoSpi to Create $500m Green Hedge Fund Focusing on the Carbon Credit Market
8. Boeing Flight Boosts Carbon Fiber Hopes, Knoxville-Oak Ridge Innovation Valley Poised
9. Reportlinker Adds Carbondioxide Incubators - A Global Market Perspective
10. North Carolina Based Cromoz Inc. Launches Carbon Nanotechnology for Target Drug Delivery System in Cancer Treatment in Hyderabad, India
11. MACTEC and MGM Innova Announce Strategic Alliance in Carbon Management Services
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Extreme darkness: Carbon nanotube forest covers NIST's ultra-dark detector
(Date:9/22/2017)... United States (PRWEB) , ... September 22, 2017 ... ... medication for venous leg ulcers is now being assessed in clinical trials in ... clinical trial please talk to your nurse or physician or find your nearest ...
(Date:9/21/2017)... ... September 21, 2017 , ... ... who enable the world’s most progressive pharma and biotech organizations to do more ... top pharma and biotech events in Q4. , DrugDev will demonstrate DrugDev Spark™, ...
(Date:9/20/2017)... ... ... The award-winning producers behind the American Farmer series proudly ... at helping farmers solve the problem of nitrogen loss. The upcoming episode is ... RFD-TV. Check your local listings for more info. , As a global ...
(Date:9/20/2017)... , ... September 20, 2017 ... ... published findings of a study examining the effects of exoskeleton-assisted walking on ... cord injury (SCI). The article, "Neuromechanical adaptations during a robotic powered exoskeleton ...
Breaking Biology Technology:
(Date:7/20/2017)... July 20, 2017 Delta (NYSE: DAL ) customers ... Delta aircraft at Reagan Washington National Airport (DCA). ... Delta launches biometrics to board aircraft ... Delta,s biometric boarding pass ... is now integrated into the boarding process to allow eligible Delta ...
(Date:6/23/2017)... ITHACA, N.Y. , June 23, 2017  IBM ... in dairy research, today announced a new collaboration using ... the chances that the global milk supply is impacted ... project, Cornell University has become the newest academic institution ... Chain, a food safety initiative that includes IBM Research, ...
(Date:5/23/2017)... robotic gym for the rehabilitation and functional motor sense evaluation of lower ... . The first 30 robots will be available from June in ... The technology was developed and patented at the IIT laboratories and has ... to a 10 million euro investment from entrepreneur Sergio Dompè. ... ...
Breaking Biology News(10 mins):