RALEIGH — A large, imposing device sits in the middle of a lab at North Carolina State University’s Centennial Campus. The device could be described as a cross between a futuristic weapon of sorts, a relic of heavy industry and a small kitchen on steroids.
“Yeah, people are a little blown away when they visit the lab,” admits Gabrielle Foley, a Ph.D. candidate in materials science. “This large steel ball is a vacuum chamber and this is where the laser hits.”
She then points to a large, gray, metal box with a bright yellow and red “danger” sign stuck on the side.
“That’s the laser, and the beam comes out of a small window in the front, travels through a series of mirrors and paths, and goes into the vacuum chamber," explains Foley, as she points out the path. “And we put our targets in the vacuum chamber.”
Scientists are using the device to create a new state of carbon not found in nature.
“It’s exciting, because it’s really new to the scientific world and it will make a really big impact on the semi-conductor industry,” says Ariful Haque, a materials science graduate student.
Carbon is one of the most common elements on the planet. The new phase of carbon they’ve discovered is called Q-carbon, and it looks a lot like a diamond. The creation of Q-Carbon is a scientific discovery in the purest sense of the word: this odd new type of carbon that's harder and brighter than a diamond, wasn’t supposed to be there.
“The first time when we got the result we were really happy about it, but then we tried many tests on the subject because what we found are new things in the scientific world,” says Anagh Bhaumik, who is also a graduate student working on the project. “We kept checking and checking to make sure.”
The research team was studying how to make diamonds in the lab without the extreme temperatures and pressures that are required in nature. They’ve been working on the project for decades. But this time, at room temperatures, they tried blasting carbon with a laser.
“We heat up carbon so high, for a very short time, and this carbon becomes a metal, which means the atoms are packed really close together,” explains Dr. Jagdish Narayan, professor of materials science and engineering at NC State Univeristy. “And then we quench it, or cool it, and by quenching, we can turn it into diamond or this new phase we’re calling Q-phase, which has some very interesting properties. The speed of the cooling process essentially fools mother nature. The melted carbon means the bonds between atoms are shortened and the quick cooling keeps them close."
Narayan adds, “We want to do it very fast: these are 20 nanosecond lasers, and in 200 nano seconds, the whole thing is completed. We’re talking very quick. In 1/5 of a microsecond or 1/5 of a millionth of a second, we complete this process. But we use the equivalent of 20 nuclear reactors, the power we put in is so much.”
That results in Q-carbon being super dense and super hard. It is harder than a diamond. Those atomic changes also mean Q-carbon emits a small amount of light, and the new state of carbon is also magnetic.
Because of its properties, the new state, or new structure, of carbon could prove extremely valuable in the electronics industry.
But for now, Dr. Narayan and his team are concentrating on making diamonds. Currently, the diamonds in the new phase of carbon are extremely small. The largest is about 70-microns wide; that’s about the width of a human hair. Researchers hope to make larger diamonds, which could be used in a host of products, including nano needles and micro needles, which have applications in electronics, industry and medical devices.
“That’s why we call it room temperature processing because the overall increase in temperature is only five degrees,” says Narayan. “The entire process is only one-fifth of a microsecond. But in that short amount of a time we can manipulate atoms and create all these new materials. It’s a new material that opens up all types of new fields.”