To make a better optical fiber for transmitting laser beams, the first idea that comes to mind is probably not a nice long hydrogen bath.
And yet, scientists have known for years that hydrogen can alter the performance of optical fibers, which are often used to transmit or even generate laser light in optical devices. Researchers at the National Institute of Standards and Technology (NIST) have put this hydrogen "cure" to practical use, making optical fibers that transmit stable, high-power ultraviolet laser light for hundreds of hours.
This is a micrograph of an optical fiber that has been infused with hydrogen and cured with ultraviolet light (here shown transmitting violet laser light.) Fibers treated this way can transmit stable, high-power ultraviolet laser light for long periods of time, resisting the damage usually caused by UV light. The diameter of the pattern of air holes surrounding the core is 62.5 micrometers.
NIST scientists expect these hydrogen-treated fibers, described in Optics Express,* to reduce errors in logic operations in their quantum computing experiments.
Optical fibers generally are not able to transmit ultraviolet light because the short wavelength light can interact with dopants or impurities in the fibers, resulting in so-called "solarization" damage and extreme losses of beam intensity. The fibers effectively shut down. Hydrogen molecules have been shown to heal this damage as it occurs.
NIST researchers tested two types of fibers with solid cores made of fused silica surrounded by lattices of air holes, which form a crystal structure that maintains the shape of transmitted laser beams. The fibers were infused with hydrogen gas at 100 times standard atmospheric pressure for four to six days.
Conveniently, some of the fibers could be treated in NIST's hydrogen pipeline materials testing facility.** After the hydrogen diffused into the fiber cores, the fibers were cured by exposure to ultraviolet laser light for several days.
NIST researchers then tested the fibers by transmitting ultraviolet laser light through them. The fibers did not display any solarization damage, even at output powers as high as 125 milliwatts (mW) at 313 nanometer (nm) laser wavelengths—several times the beam intensity needed for the group's quantum computing experiments. The combination of hydrogen infusion and curing with ultraviolet light "appears to confer long-term resistance" to this type of damage, according to the paper. The fibers also lose very little of the laser light as it is transmitted.
For comparison, NIST researchers also tested fibers that were not treated with hydrogen. With 313 nm wavelength laser light at 100 mW power, light transmission through the fibers dropped to zero in four hours, confirming the value of the hydrogen treatment.
The treated fibers could be used to transmit a wide range of infrared, visible and ultraviolet wavelengths of light, according to the research team. When used at NIST to transmit laser light to trap ions (electrically charged atoms), the fibers reduce stray light and fluctuations in laser beam pointing and make it possible to transfer ultraviolet light between separate optical tables, the paper notes. The fibers also can help "clean up" misshapen beams, the researchers say.
The same NIST research group has achieved many "firsts" using trapped ions to demonstrate building blocks for quantum computers, which would use the exotic properties of the quantum world to solve problems considered intractable today.
* Y. Colombe, D.H. Slichter, A.C. Wilson, D.G. Leibfried and D.J. Wineland. Single-mode optical fiber for high-power, low-loss UV transmission. Optics Express, Vol. 22, Issue 16, pp. 19783-19793. Published online Aug. 8, 2014. DOI:10.1364/OE.22.019783.
** See 2010 NIST Tech Beat article, "Future of Hydrogen Fuel Flows Through New NIST Test Facility," at http://www.nist.gov/public_affairs/tech-beat/tb20100216.cfm#hydrogen.
Laura Ost | Eurek Alert!
Artificial Intelligence Helps in the Discovery of New Materials
21.09.2016 | Universität Basel
Magnetic polaron imaged for the first time
19.09.2016 | Aalto University
The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.
“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...
With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.
Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...
For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.
Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...
At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.
In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...
Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.
K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...
23.09.2016 | Event News
20.09.2016 | Event News
16.09.2016 | Event News
23.09.2016 | Life Sciences
23.09.2016 | Health and Medicine
23.09.2016 | Life Sciences