Rowan Physics: Hot lasers, cool plasma

Physical scientists at Rowan University probe the secrets of matter with laser beams and an electron microscope.

In a climate-controlled laboratory in Science Hall, physics majors and faculty use million-dollar laser equipment to study super cold plasmas, gas-like clouds of charged particles that may mimic matter within giant planets.

Across the hall, researchers experiment with diamond-like materials as possible coatings for cubic zirconia, where the process is designed to make the white, yellow and pink man-made gemstones harder and richer.

Nearby, experimenters work to change the color of natural pearls from white to gold, a process that, if successful, could be worth a fortune.

And, in the same room, students and faculty apply films to atomically flat wafers of sapphire. The films, including chromium, vanadium, aluminum and carbon atoms, create impossibly thin ceramic coatings that could one day sheathe engine parts, turbines or satellite components. Potential for the so-called thin-film ceramics, which marry the mechanical properties of glass with the electrical properties of metals, could be infinite. Glass films, also synthesized at Rowan, may one day line the inside of cans of Coke, plastic bags or plastic wrappers to better protect their contents.

“The process works sort of like this,” explained Dr. Jeffrey Hettinger, professor of physics and chair of the department. “First we make stuff, and then we study the properties of what we make.”

Though the physics department isn't large -- it contains roughly 80 majors - it is steeped in highly technical research funded in part by the National Science Foundation and the U.S. Department of Energy.

In the past two years roughly 25 percent of the department's students published in academic journals and two especially gifted students, Andrew Robertson ('07) and Lucas Willis ('08), earned fully-paid National Defense Science and Engineering Graduate fellowships.

Robertson is pursuing his doctorate in physics at the University of Maryland while Willis will begin work toward his Ph.D. at Yale University this September. Willis, whose research will focus on atomic physics, seeks a career in academia or with a national laboratory.

Surprisingly, the physics/math double major said he wavered before attending Rowan (the only school he applied to) and instead nearly took a job in construction. Once on campus, however, the research bug bit him, and hard.

"You come into a room like this," said Willis, 22, of Bellmawr, looking about the laser lab, "and you feel this is really cool. This is something I can do."

Laser-guided education

Indeed, access to a fully operational laser lab as well as a microscopy lab with electron microscope amounts to a double dose of cool for student researchers. It's the type of equipment students generally don't have access to until graduate school.

The laser lab features a dozen beams of varying strength that are used for a variety of experiments including the study of super cold plasmas, a collection of charged particles with properties unlike typical gases, solids or liquids.

Prof. Michael Lim said students and faculty actually produce plasma in the laser lab that might be similar to plasmas found in space.

"We do something called laser cooling of atoms," said Dr. Lim. "The photons -- particles of light the laser beam is made of -- can slow the motion of atoms and that is what cools them."

He said naturally occurring plasma is typically hot - about 1,000 degrees Kelvin or hotter while plasma produced in his lab is about 1 degree Kelvin (-458 degrees Fahrenheit.)

"The idea here is to learn," Lim said. "We can probably learn something about that class of plasmas by what we make here in the lab."