January 18, 2011

By Benjamin White

NQPI member Wojciech Jadwisienczak of the Russ College of Electrical Engineering and Computer Science was recently awarded a National Science Foundation Career Grant of $444,000 over five years to study new materials for use in future optoelectronics, photonics and spintronics.

Dr. Jadwisienczak, known as “Dr. J” around campus, teaches undergraduate and graduate courses and studies semiconductor materials, their devices and related technologies. The central focus of his research is the incorporation of rare-earth ions in III-Nitride semiconductors and their alloys. These ions (typically RE (3+)) have several interesting and profitable traits like producing a very pure color when excited by different means, including electrical current. The III-Nitrides technology has already hit the market in the form of Blu-ray players, which use a very small pure blue laser to read information packed into smaller chunks than DVDs.

One of Dr. Jadwisienczak's goals is to study materials which contain different rare earth ions and have interesting optical and magnetic properties. For example, Erbium, one of the most intriguing members of the lanthanide family, emits light at the wavelengths used by fiber optic cables, so it could prove to be very valuable in the telecommunications field due to an expected reduction in signal attenuation. Dr. Jadwisienczak explained that scientists have been trying to harness and use the strange properties of the rare-earth ions that occur naturally.

“We are simply lucky to have this opportunity, a case of an Erbium ion electron energy level fitting exactly to the telecommunication window,” explained Dr. Jadwisienczak. “Recent successes in developing Erbium-doped silicon-based compounds give hope that one day this opportunity will become a reality.”

Rare-earth ions could possibly also be used to overcome the current limitations of the III-Nitride technology in producing red light emitting diodes (LEDs). For quite a long time, scientists have been attempting to fabricate an InGaN alloy having the high indium content necessary to generate red light needed for a full technological integration of all primary colors. It was not possible until recently, when a group of researchers in Japan engineered a way to efficiently use Europium, another rare-earth element, to produce very pure red LEDs.

When scientists find a way to create the three primary colors efficiently, they could make ultra-small LEDs which could improve technology, creating a new generation of high-definition flat TV screens and displays.

Currently, blue, green and red lasers use different semiconductors, but Dr. Jadwisienczak envisions a “one-pot” model in which materials emitting the three primary colors could be created using the same growth system. He also aims to increase the energy efficiency of the light emitters based on rare earth-doped III-Nitrides operating in ultraviolet and near the infrared spectral range.

Dr. Jadwisienczak has collaborated with NQPI partners on projects related to materials growth, characterizations and device development for more than a decade. Especially, he says, his alliances with NQPI professors Arthur Smith, Marty Kordesch and Savas Kaya, to mention only a few, are important for the success of his CAREER project thanks to existing collaborative efforts and shared visions in research.

The National Science Foundation's Career Grants are highly selective and only available to non-tenured researchers.

Please see OU Office of Research's article: Engineering Profs Receive NSF CAREER Grants for Nanotechnology Research.