Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Just one nanosecond: Clocking events at the nanoscale


As scientists and engineers build devices at smaller and smaller scales, grasping the dynamics of how materials behave when they are subjected to electrical signals, sound and other manipulations has proven to be beyond the reach of standard scientific techniques. But now a team of University of Wisconsin-Madison researchers has found a way to time such effects at the nanometer scale, in essence clocking the movements of atoms as they are manipulated using electric fields.

The accomplishment, reported in the most recent edition (May 12, 2006) of the journal Physical Review Letters, is important because it gives scientists a way to probe another dimension of a material’s structure at the scale of nanometers. Adding the dimension of time to their view of the nanoworld promises to enhance the ability to develop materials for improved memory applications in microelectronics of all kinds, among other things.

"Now we have a tool to look inside a device and see how it works at the spatial scale of nanometers and the time scale of nanoseconds," says Alexei Grigoriev, a UW-Madison postdoctoral fellow and the lead author of the Physical Review Letters paper.

With the advent of nanotechnology, the ability to make devices and products on a scale measured in atoms has mushroomed. Already, products with elements fabricated at the nanoscale are on the market, and scientists continue to hone the technology, which has potential applications in areas ranging from digital electronics to toothpaste.

The traditional tools of nanotechnology -- the atomic force microscope and the scanning tunneling microscope -- enable scientists to see atoms, but not their response to events, which at that scale occur on the order of a billionth of a second or less.

The ability to time events that occur in materials used in nanofabrication means that scientists can now view dynamic events at the atomic scale in key materials as they unfold. That ability, in turn, promises a more detailed understanding -- and potential manipulation -- of the properties of those materials.

The Wisconsin work was accomplished using Argonne National Laboratory’s Advanced Photon Source, a synchrotron light source capable of generating very tightly focused beams of X-rays. The Wisconsin researchers, in a group led by materials science and engineering Professor Paul Evans, focused a beam of X-rays on a thin film of a ferroelectric material grown by another Wisconsin group led by materials science and engineering Professor Chang-Beom Eom.

The X-rays, according to Grigoriev, are delivered to the sample in fast pulses over an area no larger than hundreds of nanometers, one ten-millionth of a meter.

Ferroelectric materials respond to electric fields by expanding or contracting their crystal lattice structures. Ferroelectric materials also exhibit the property of remnant polarization, where atoms are rearranged in response to electrical signals. This property allows tiny ferroelectric crystals to be used as elements of digital memories.

"Physically, the atoms switch position," Grigoriev explains. "And as devices are pushed to smaller sizes, they must switch in extremely short times. It requires new tools to see those dynamics."

Using the X-rays from the Advanced Photon Source and measuring how the X-rays were reflected as the atoms in the material switched positions, the Wisconsin researchers were able to clock the event.

As a material is subjected to the X-rays and the electrical signals, "you can see in time how the crystal structure (of the material) changes as the switching polarization propagates through the lattice," Grigoriev explains.

The technique developed by Evans, Grigoriev and their colleagues is a combination of two existing techniques, making the technology easily accessible to science. It might also be applied to studies of phenomena such as magnetism and heat dissipation in microelectronic structures.

Alexei Grigoriev | EurekAlert!
Further information:

More articles from Physics and Astronomy:

nachricht Novel light sources made of 2D materials
28.10.2016 | Julius-Maximilians-Universität Würzburg

nachricht OU-led team discovers rare, newborn tri-star system using ALMA
27.10.2016 | University of Oklahoma

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: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Steering a fusion plasma toward stability

28.10.2016 | Power and Electrical Engineering

Bioluminescent sensor causes brain cells to glow in the dark

28.10.2016 | Life Sciences

Activation of 2 genes linked to development of atherosclerosis

28.10.2016 | Life Sciences

More VideoLinks >>>