Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ultrafast laser technique developed to observe electron action

13.05.2014

University of Central Florida physicist Zenghu Chang has done it again. For a third time this year, his research group has published an article in a Nature journal.

This time, Chang and his team have developed a new ultrafast light source for observing electron motion in molecules – made up of nuclei and electrons – at the point before the nuclei start to move. By being able to observe what actually happens, scientists can begin to understand how an electron interacts with other electrons, which may help improve the efficiency of solar cells.


This is Zheng Chang in his lab at UCF.

Credit: UCF

"The charge migration that theorists have been predicting since 1999 happens so quickly we haven't been able to observe it yet," Chang said. "It's very exciting, because we have found a new way to build light sources that may allow us to see it in the future."

Being able to see this superfast interaction between electrons gives scientists another tool to unlock the rules that govern the quantum-mechanics world – a world where microscopic objects don't obey the laws of physics we have come to rely on for understanding in the macro world.

So how did Chang and his team manage to develop the new light source? The team borrowed an idea from Chang's earlier innovative work in the area of ultrafast lasers.

"We control the below-threshold harmonic light emission by using electromagnetic fields with time-dependent ellipticity, like we have done to the above-threshold high-order harmonics," said Chang referring to the creation of a 67-attosecond pulse of extreme ultraviolet light, which earned him international recognition. "We thought: Could we use the same gating fields to show the dependence of the below-threshold harmonic intensity on the carrier-envelope phase of the driving laser? It took us some time to find the right experimental parameters, but the answer is yes."

The result of his study "Coherent phase-matched VUV generation by field-controlled bound states" appears this week in Nature Photonics.

Chang has been studying light and ultrafast lasers his entire career. This past year UCF established the Institute for the Frontier of Attosecond Science and Technology (FAST). The institute is a collaboration between experts and students in UCF's College of Optics and Photonics (CREOL) and the College of Sciences' physics department to focus on this field of science.

Co-authors include: Michael Chini, Xiaowei Wang, Yan Cheng, Yi Wu and Eric Cunningham from UCF's FAST; Peng-Cheng Li, John Heslar and Shih-I Chu from the Center for Quantum Science and Engineering and the Department of Physics at the National Taiwan University; He Wang from the Materials Sciences Division at the Lawrence Berkeley National Laboratory, and Dmitry A. Telnov from the Department of Physics at St. Petersburg State University in Russia.

"It was truly a collaborative effort," Chang said. "And there are certainly commercial applications. We're talking about cutting-edge lasers with potential application in electronics, navigation, communications and medicine."

Chang said he is excited about the new work because he hopes it will help lead to bigger and greater discoveries.

"My dream is to discover new physics that has not been predicted at this time," Chang said. "Until there was a microscope, we had no idea how complicated, how amazing cells were. What we are creating now are tools for magnifying time in order to discover what we have not even imagined yet. That's what I see for the future of our field."

###

The Defense Advanced Research Projects Agency, National Science Foundation, U.S. Department of Energy, National Science Council of Taiwan and National Taiwan University funded the research.

America's Partnership University: The University of Central Florida, the nation's second-largest university with nearly 60,000 students, has grown in size, quality, diversity and reputation in its first 50 years. Today, the university offers more than 200 degree programs at its main campus in Orlando and more than a dozen other locations. UCF is an economic engine attracting and supporting industries vital to the region's future while providing students with real-world experiences that help them succeed after graduation. For more information, visit http://today.ucf.edu.

Zenaida Kotala | Eurek Alert!

Further reports about: Photonics Physics Quantum UCF Ultrafast electrons lasers nuclei physics technique

More articles from Physics and Astronomy:

nachricht Neutron star merger directly observed for the first time
17.10.2017 | University of Maryland

nachricht Breaking: the first light from two neutron stars merging
17.10.2017 | American Association for the Advancement of Science

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>