Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Turning metal black more than just a novelty

10.12.2009
University of Rochester scientists discover that laser technique used to change the colors of metals could have important implications for medicine

University of Rochester optics professor Chunlei Guo made headlines in the past couple of years when he changed the color of everyday metals by scouring their surfaces with precise, high-intensity laser bursts.

Suddenly it was possible to make sheets of golden tungsten, or black aluminum.

A recent discovery in Guo's lab has shown that, beyond the aesthetic opportunities in his find lie some very powerful potential uses, like diagnosing some diseases with unprecedented ease and precision.

Along with his research assistant, Anatoliy Vorobyev, Guo has discovered that the altered metals can detect electromagnetic radiation with frequencies in the terahertz range (also known as T-rays), which have been challenging, if not impossible, to detect prior to his discovery.

"When we turned metals black, we knew that they became highly absorptive in the visible wavelength range because the altered metals appear pitch black to the eye. Here, we experimentally demonstrated that the enhanced absorption extends well into the far infrared and terahertz frequencies," Guo said.

With wavelengths shorter than microwaves, but longer than infrared rays, T-rays occupy a place in the electromagnetic spectrum that is capable of exciting rotational and vibrational states of organic compounds, like pathogens. This quality could allow doctors and biomedical researchers to get previously impossible glimpses of diseases on the molecular level.

In addition, unlike X-rays, T-rays are non-ionizing, which means that people who are exposed to them don't risk the possible tissue damage that can result from X-rays.

University of California, Berkeley, bioengineering Professor Thomas Budinger says terahertz radiation is like much-higher-frequency radar, except that it theoretically can allow its users to see intricate details of tissue architecture, on the scale of one-thousandth of a millimeter and smaller, instead of large objects like airplanes and boats.

"Terahertz electromagnetic radiation has the capability to interrogate tissues at the cellular level. If applied within microns of the subject of interest, this form of imaging has the theoretical capability to detect properties of molecular assemblages that could be attributes of disease states," Budinger said.

What made terahertz radiation so difficult to detect in the past was that typical materials do not readily absorb that frequency. However, after undergoing Guo's femtosecond structuring technique, metals become over 30 times more absorptive.

The key to creating the black metal in terahertz is a beam of ultra-brief, ultra-intense laser pulses called femtosecond laser pulses. The laser burst lasts less than a quadrillionth of a second. To get a grasp of that kind of speed, consider that a femtosecond is to a second what a second is to about 32 million years. During its brief burst, Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point. That intense blast forces the surface of the metal to undergo some dramatic changes and makes them extremely efficient in absorbing terahertz radiation.

About the University of Rochester
The University of Rochester is one of the nation’s leading private universities. Located in Rochester, N.Y., the University gives students exceptional opportunities for interdisciplinary study and close collaboration with faculty through its unique cluster-based curriculum. Its College, School of Arts and Sciences, and Hajim School of Engineering and Applied Sciences are complemented by the Eastman School of Music, Simon School of Business, Warner School of Education, Laboratory for Laser Energetics, Schools of Medicine and Nursing, and the Memorial Art Gallery.

Alan Blank | EurekAlert!
Further information:
http://www.rochester.edu

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 >>>