Zinc Oxide Microwires Improve LED Performance Through Piezo-Phototronic Effect

Zinc oxide microwires were used by Georgia Tech researchers to improve the efficiency at which gallium nitride light-emitting diodes (LEDs) convert electricity to ultraviolet light. By applying mechanical strain to the microwires, the researchers created a piezoelectric potential in the wires, and that potential was used to tune the charge transport and enhance carrier injection in the LEDs. This control of an optoelectronic device with piezoelectric potential — or piezo-phototronics — represents another example of how materials that have both piezoelectric and semi conducting properties can be controlled mechanically.