Assistant Professor
Department of Materials Science and Engineering

Chekesha Liddell’s research centers on the creation and characterization of nano- and meso-scale inorganic colloids with tailored morphology and composition, as well as the fabrication of three-dimensional structures derived from these colloidal building blocks.

The objective is to fashion artificial crystal structures using inorganic particles, focusing on non-spherical shapes. Reducing the symmetry in such structures promotes a significantly higher level of control of light waves.

“This work examines the structural coloration effects that result from the interaction of light waves and objects that are similar in size to the wavelengths. You can see this effect in peacock feathers viewed under a microscope,” she explains.

Similarly, in the gemstone opal, the coloration changes with the angle of view. That effect is caused by an array of silicon particles, or organized crystal structures, that perform light refraction.

Liddell primarily uses photonic band gap materials, or photonic crystals, which behave similarly to the electrons in a semiconductor, except that the photon carries the data instead of an electron. Applications for such materials include optical computing switches that may replace electronic switches, lasers, and light-emitting diode (LED) devices.

“This would enable faster and more efficient computing hardware,” Liddell says. The principles involved have been demonstrated in two-dimensional and three-dimensional photonic crystals, ranging in size from 100 nanometers to a few microns.

Three-dimensional photonic crystals also can be used in the design and synthesis of colloids for environmental remediation efforts, mesoscale assembly techniques, colloid separations technology, hierarchical inorganic and hybrid bio-inspired materials and matter-energy interactions for ion beam modification of colloids.

“The work is challenging,” says Liddell, “because we are creating designs based on particle size, shape, and chemical composition. The goal is to tailor the properties of these structures for specific uses.”

Liddell earned a Ph.D. in materials science and engineering, with a minor in science and technology policy from Georgia Tech University. She also held three internship appointments at NASA. She teaches an introduction to ceramics course as well as a course on colloids and colloid assemblies.

Professor Liddell's Web site