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This is a brief video. Maybe I am overwhelmed by this because of my chemistry background, but in my opinion, this video documents what truly should be “wow”-level historical type of moment in material-related sciences. As the folks at the Lawrence Berkeley Nation Lab note, this is equivalent to the first biologist who peered through a microscope and saw a cell divide.

To summarize, this video is no more, or less, than watching for the first time, in real-time, individual carbon atoms being knocked off the edges of a hole in a sheet of graphene while other atoms break and recreate bonds as they shift around in response, looking for the most stable position. The video also contains a simulation of what is occurring (created using a Monte Carlo simulation method to “orchestrate” which carbon atoms leave and which shift).

And, like all really great movies, it’s hard to tell who deserves more credit: The actors or the director and cinematographers? The analogy isn’t perfect, but as awesome as this movie is, what is equally amazing is the incredible electron microscope behind the movie - TEAM 0.5.

TEAM 0.5, which just recently became operational, is the world’s most powerful electron microscopy. The technology behind TEAM 0.5 come from a team that includes the Berkeley, Argonne and Oak Ridge National Labs, the Frederick Seitz Materials Lab of the University of Illinois, and two electron microscopy companies, FEI (Portland) and CEOS of (Heidelberg).

In some ways, researchers are just starting to “play” with TEAM and are already planning on using it on other structures and materials. Nevertheless, this first video is providing new leads and confirmations to those studying spin properties in atoms.

Researchers say that logic and memory functions of future electronic devices could shrink an order of magnitude (one or two nanometers, instead of tens of nanometers) if they can control domain walls, the transition zones in a material that separate regions of different magnetic, electric or other properties. And, by “control,” the researchers remarkably mean “writing,” “erasing” and moving the domains.

While studying bismuth ferrite (BiFe0₃), scientists at the Lawrence Berkeley National Laboratory and the University of California, Berkeley discovered an amazing property of domain walls. They found that within the material, between domains having different electrical polarization, the domain walls themselves – just a few nanometers wide – can be made to conduct electricity.

Ramamoorthy Ramesh of Berkeley Lab’s Materials Sciences Division, a professor in the Department of Materials Science and Engineering and the Department of Physics explains, “A domain wall is virtually a two-dimensional sheet through the material.” He says that besides being small, they can be moved, and thus offer great promise in future electronics design.

Ramesh says that the basic electrical and magnetic properties of a complex material such as bismuth ferrite are extremely sensitive to their environment. “Materials called multiferroics are an example of this kind of material, and bismuth ferrite is a prototypical multiferroic.”

A unique property of multiferroic materials is that they can have different properties within certain regions that are differently oriented, but not independent. “One reason we are looking at oxides like bismuth ferrite is because we can control one property by changing others,” says Ramesh. “These materials have a lot of personality.”

To make films of the material, researchers hit targets of ceramic oxides containing bismuth and iron with a laser pulse that causes a deposit to form on the substrate. They manipulate the substrate structure, temperature and atmosphere to get the sought after mix and phase.

Fifty to 200-nanometer films of bismuth ferrite have been grown substrates of strontium titanium oxide.

Bismuth ferrite has the crystal structure of perovskite. The bismuth ferrite films contain ferroelectric domains between 5 and 10 micrometers that can be mapped using a piezoresponse force microscope. Furthermore,  the domain structure can be changed by using different scanning-probe mechanisms. For example, the PFM setup can switch the local polarization of the film by applying a large enough voltage.

“We worked with theorists to help us model the behavior we had observed and to understand the mechanism of the conduction,” says Ramesh. “What happens is that as the positions of the central iron atoms change crossing the domain wall, the polarization increases perpendicular to the domain wall – but at the same time goes to zero parallel to the wall, before increasing again,” says Martin. “This causes any free electrons in the vicinity to accumulate at the wall, where they can move along the wall itself.”

“Domain walls may be the ultimate nanoscale feature,” says Lane Martin of MSD. “They’re intrinsic to the material – they want to be there. And they’re only two nanometers wide! It’s like shoving a graphene sheet right down into a tough, insulating ceramic.”

For Ramesh, the discovery is big step on “the path to the Holy Grail of oxide materials, the challenge of creating and controlling metal-insulator transitions at interfaces in a material. It’s why DOE is so interested in this kind of research.”

There’s a ripple of excitement in the science and technical community. Imagine - an experienced scientist and successful administrator with a breadth of knowledge at the helm of the Department of Energy. Given the role DOE is going to play in the next few years, the selection of Steven Chu comes at a critical time. Since 2004, he has been the director of the Lawrence Berkeley National Lab where where was a strong support of research on alternative energies and understood the links to global warming. Here is a revealing video featuring Chu. I find it especially heartening that he understands standards, regulations and the difference between lobbyists are allowed to muck up engineering challenges: Update: More good info, videos and links on Chu here and here.