Light Exposure Increases Crystal's Electrical Conductivity 400-fold [VIDEO]
Scientists accidentally discovered a way to increase the conductivity of a crystal known as strontium titanate by 400 times, a study published in the journal Physical Letters Review found.
"It came by accident," doctoral student Marianne Tarun said in a statement. "It's not something we expected. That makes it very exciting to share."
Tarun noticed by chance that the crystal's conductivity shot up after being left out one day. Though she and her colleagues thought it was contaminated at first, a series of experiments identified light as the source of the change.
The phenomenon is called persistent photoconductivity, and while still a long ways off from a total lack of electrical resistance, known as superconductivity, the fact that the process took place at room temperature makes it highly practical, the researchers explain.
"The discovery of this effect at room temperature opens up new possibilities for practical devices," said Matthew McCluskey, co-author of the paper and chair of the school's physics department. "In standard computer memory, information is stored on the surface of a computer chip or hard drive. A device using persistent photoconductivity, however, could store information throughout the entire volume of a crystal."
Called holographic memory, the approach could mean a dramatic rise in information capacity, McCluskey explained.
What's more, a little goes a long way the researchers discovered when they held up a sample to light for 10 minutes and observed as its improved conductivity lasted for days.
The improvement could be the result of the the light freeing the material's electrons, they theorize.
Strontium titanate and other oxides cover the gamut when it comes to electronic phenomena, from very high to a complete lack thereof.
"These diverse properties provide a fascinating playground for scientists but applications so far have been limited," McCluskey said.