Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Laser-Created Temporal Lens Could Lead to Movies of Molecular Processes

01.07.2009
A team at the University of Nebraska-Lincoln has figured out a possible way to observe and record the behavior of matter at the molecular level. That ability could open the door to a wide range of applications in ultrafast electron microscopy used in a large array of scientific, medical and technological fields.

Finding a way to observe and record the behavior of matter at the molecular level has long been one of the holy grails among physicists. That ability could open the door to a wide range of applications in ultrafast electron microscopy used in a large array of scientific, medical and technological fields.

Now, a team at the University of Nebraska-Lincoln has figured out a possible way to do that. Working in collaboration with Nobel laureate Ahmed Zewail (chemistry, 1999) of the California Institute of Technology in Pasadena, they developed mathematical models to show that laser beams create ultra-high-speed "temporal lenses" that would be capable of making "movies" of molecular processes. The finding was published in the June 15-19 online edition of the Proceedings of the National Academy of Sciences.

The "lenses" in question are not made of glass like those found in standard tabletop microscopes. They're created by laser beams that would keep pulses of electrons from dispersing and instead focus the electron packets on a target. The timescales required, however, are hardly imaginable on a human scale -- measured in femtoseconds (quadrillionths of a second) and attoseconds (quintillionths of a second).

Herman Batelaan, associate professor of physics at UNL, said the process is analogous to filming the flight of a thrown baseball. First, the camera lens must be focused properly or the ball will appear blurred. Second, the camera has to have a fast shutter speed or the seams of the ball will appear streaked. But the analogy stops there.

Two other analogies help illustrate the timescales Batelaan and his colleagues are grappling with. A standard comparison is that one attosecond is to one second as one second is to the age of the universe. Another is that one attosecond is to one second as the volume of one grain of sand is to the volume of all the water in all of the oceans of the world.

"The timescales involved here are daunting," Batelaan said. "A crisp image of the seams of a thrown baseball can be made with a strobe pulse of about one 10 millionth of a second. Taking a crisp image of an atom in a molecule is much more demanding. Pulses that are a billion times shorter than that are needed. Anything produced to date is 50 times slower than that and making movies of most molecules has stayed out of reach.

"The new idea is that a temporal lens exists and obeys the same laws as a spatial lens. That's what we showed in this paper. Nobody had ever used a temporal lens to get a higher resolution."

The physicists modeled two types of lenses. One was a temporal "thin" lens created using one laser beam that could compress electron pulses to less than 10 femtoseconds. The second was a "thick" lens created using two counterpropagating laser beams that showed the potential of compressing electron pulses to reach focuses of attosecond duration.

"The thick lens will give the best value, but it's much more complex, because the attosecond regime is three orders of magnitude smaller than the femtosecond regime," said Shawn Hilbert, the paper's lead author and a May Ph.D. graduate under Batelaan.

"It's great that we were able to take a very simple idea -- at least in physics -- and produce a paper like this," Hilbert said. "The lensmakers equation is something you learn in intro to optics, so pretty much any undergrad in physics learns this stuff. But now we've applied it to time, which no one has ever thought of in this way before. You could explain this to intro undergraduate students and they would get the idea. It's very simple, but it's also very powerful."

In addition to Hilbert (a native of Hanover, Pa., who will begin a tenure-track faculty position at Texas Lutheran University in the fall) Batelaan and Zewail, the other co-authors of the paper are Cornelis "Kees" Uiterwaal, associate professor of physics at UNL, and Brett Barwick, a postdoctoral scholar with Zewail at Cal Tech. Barwick earned his Ph.D. at UNL, studying quantum optics with Batelaan from 2002 to 2007, before going on to Zewail's lab, and provided the critical bridge to bring the collaboration about.

"He (Zewail) called us and said, 'Hey, do want to work with us?'" Batelaan said. "He knew that with Brett, we had developed techniques that allowed us to explore this kind of research. He asked if we could go further with this application because the Cal Tech people want to use it to make movies of molecular processes.

"We've been looking through cloudy lenses in a pair of glasses. Now, we've figured out that there is such a thing as clear glasses. I think it's really cool."

The research was supported by funding from the National Science Foundation, the Air Force Office of Scientific Research in the Gordon and Betty Moore Center for Physical Biology at Cal Tech, and the Nebraska Research Initiative.

Tom Simons, Unversity of Nebraska-Lincoln 402-472-8514, tsimons1@unl.edu
Herman Batelaan, Assoc. Professor, Physics and Astronomy, (402) 472-3579, hbatelaan2@unl.edu

Tom Simons | Newswise Science News
Further information:
http://www.unl.edu

More articles from Physics and Astronomy:

nachricht Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory

nachricht SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>