clock menu more-arrow no yes

Filed under:


Stephen Bialkowski is as excited about what he does as the tiny molecules of gas he excites with his laser beams.

The Utah State University chemist is studying how lasers excite certain gases, and his work has a variety of potential uses and applications.Bialkowski said the laser technique enables ultra-sensitive analysis of quantities of molecules, and the principles can also be used in switching devices, particularly in communications equipment.

At present he is looking at the excitation patterns of amounts of chlorofluorocarbons, or CFCs. CFCs have been implicated in causing the hole in the earth's ozone layer, observed at the South Pole.

Bialkowski has built his experimental laser apparatus from a variety parts. Ultraviolet and infrared waves produced by the laser excite CFC molecules. The laser is guided and focused by mirrors and lenses prepared from materials such as barium fluoride, germanium and sodium chloride.

When the CFC molecules absorb energy from a helium-neon laser beam, they expand. Expansion of the gas changes its ability to bend the light coming from the laser. Changes in the laser beam's location is picked up and measured by a photodiode.

Gas expansion and differential bending of light is the phenomenon that causes air to shimmer above a hot blacktop surface and mirages, Bialkowski said. The sun-heated blacktop heats the air, which expands and becomes thinner, bending light differently than denser air above it.

Bialkowski is comparing the results from pulsed and continuous laser of gases and is looking at the small pressure waves that are when the gases absorb energy.

He anticipates that his chemical analysis technique will have wide application in environmental problems and in the food and chemical industries.