Manufacturing Bits: June 6

Molecular black holes
A group of researchers have used an ultra-bright pulse of X-ray light to hit a tiny atom in a molecule, causing the structure to explode and create a “molecular black hole.”

The molecular black hole is different than a black hole in space, however. A black hole is a region in space, which has a gravitational field so strong that no matter or light can escape it.

In the molecular black hole experiment, though, researchers achieved what they claimed is the world’s strongest ionization of a molecule to date. This research, in turn, will provide key insights for analyzing biomolecules with X-ray lasers.

For this, researchers used a free-electron laser at the SLAC National Accelerator Laboratory. They used special mirrors to focus the X-ray beam into a spot over 100nm in diameter. The laser hit iodomethane (CH3I) molecules at pulses around 100 quadrillion kilowatts per square centimeter. The result caused a chain reaction. Some 54 of the 62 electrons were knocked out of the molecule in a trillionth of a second.

This, in turn, created a void. Then, like a black hole, the void started pulling in electrons from the rest of the molecule. The end result was a molecule carrying a positive charge 54 times the elementary charge.

The intense X-ray flash knocks so many electrons out of the iodine atom (right) such that it pulls in the electrons of the methyl group (left) like an electromagnetic version of a black hole, before finally spitting them out. (Credit: DESY/Science Communication Lab)

“As far as we are aware, this is the highest level of ionization that has ever been achieved using light,” said Robin Santra, a DESY scientist at the Center for Free-Electron Laser Science (CFEL), who is also a professor of physics at the University of Hamburg.

“The methyl group CH3 is in a sense blind to X-rays,” Santra said. “The X-ray pulse initially strips the iodine atom of five or six of its electrons. The resulting strong positive charge means that the iodine atom then sucks electrons away from the methyl group, like a sort of atomic black hole.”

Solving deadly viruses
Using X-ray beam technology, The Scripps Research Institute (TSRI) has solved the structure of the viral machinery of the deadly Lassa virus.

Lassa fever is an acute viral illness, which occurs in Africa, according to the Centers for Disease Control and Prevention (CDC). “The number of Lassa virus infections per year in west Africa is estimated at 100,000 to 300,000, with approximately 5,000 deaths,” according to the CDC.

Like Ebola virus, Lassa fever starts with flu-like symptoms. It can lead to vomiting, neurological problems and even hemorrhaging from the eyes, gums and nose. The disease is 50% to 70% fatal, according to SLAC.

To explore the structure of this virus, researchers used the Stanford Synchrotron Radiation Lightsource (SSRL) at SLAC. With this, scientists looked at the structure of the crystals. Researchers found a key piece of the viral structure. This structure, called surface glycoprotein, provides a blueprint to design a Lassa virus vaccine.

The molecular structure of a Lassa virus protein provides the blueprints for vaccine design. (Credit: Ollmann Saphire Lab/The Scripps Research Institute)

“This was a tenacious effort–over a decade–to conquer a global threat,” said Erica Ollmann Saphire, a professor of Immunology and Microbial Science from TSRI.

SSRL senior staff scientist Aina Cohen added: “This structure provides key information towards engineering an effective vaccine against Lassa, enabling the infected to combat the immunosuppressive traits of this virus, which is estimated to kill tens of thousands of people each year.”

DARPA chip funding
The U.S. Department of Defense’s proposed budget for 2018 includes a $75 million allocation for DARPA in support of a new, public-private “electronics resurgence” initiative.

The funding will enable new materials, designs, and architectures. The new funds will supplement the agency’s current portfolio in electronics, photonics and related technologies.

The materials portion of the initiative will explore the use of unconventional circuits. The research will focus on integrating different semiconductor materials. The architecture portion of the initiative will examine circuit structures that are optimized to the specific tasks they perform. The initiative will explore reconfigurable physical structures and other technologies.

The design portion of the initiative will focus on developing new EDA tools. “For nearly seventy years, the United States has enjoyed the economic and security advantages that have come from national leadership in electronics innovation,” said Bill Chappell, director of DARPA’s Microsystems Technology Office (MTO), on the agency’s Web site. “If we want to remain out front, we need to foment an electronics revolution that does not depend on traditional methods of achieving progress. That’s the point of this new initiative – to embrace progress through circuit specialization and to wrangle the complexity of the next phase of advances, which will have broad implications on both commercial and national defense interests.”