Nanostars shine in optics

New optics research from

's Laboratory for Nanophotonics suggests that tiny gold particles called nanostars could become powerful chemical sensors.

Nanophotonics is a rapidly growing field of study that looks at ways to generate and manipulate light using ultrasmall, engineered structures. The virus-sized nanostars, so named because of their spiky surface, are one of a growing number of intricately shaped particles that are increasingly drawing the attention of experts at leading photonics labs.

"Just a few years ago, everyone's attention was on the size of nanoparticles because altering size was a straightforward way to change the wavelength of light that the particle reacted with," said lead researcher Jason Hafner, associate director of LANP and assistant professor of physics and astronomy and of chemistry. "Today, researchers are increasingly interested in intricate shapes and the specific ways that those shapes affect a particle's interaction with light."

Most nanophotonic research at LANP involves the study of plasmons, waves of electrons that flow like a fluid across metal surfaces. Light can be used to amplify plasmon waves on metal nanoparticles. Plasmons on the particles are amplified with wavelengths of light that correspond to the rhythm of the electron waves. The study of plasmonics is one of the fastest growing fields in optics because it could prove useful for a wide range of applications in biological sensing, microelectronics, chemical detection, medical technology and others.