91�����

The Nobel Prize in Physics was won last autumn by Isamu Akasaki, Shuji Nakamura, and Hiroshi Amano for the development of an LED that produces blue light.  When the invention is combined with the previously developed red and green, the result is white LED light. Lamps that emit LED light are getting to be ubiquitous, and it is no wonder: compared with incandescent lights and fluorescent tubes, LEDs are overwhelming both in duration and energy-efficiency.

Aalto University Professor Filip Tuomisto, who is working on research together with Amano, knows that the upheaval in lighting did not happen easily.

"In the 1980s Amano had an especially significant role in the development of methods of manufacturing high quality gallium nitride, the semiconductor used in LEDs." Faith was needed for the whole thing to succeed, even though many other researchers had already given up and moved on to zinc selenide or silicon carbide", Tuomisto says.

Faith was needed for the whole thing to succeed.

Already before the Nobel prize Amano was one of the leading names in nitride semiconductor technology used in LEDs and lasers. Tuomisto and his group have studied the crystal quality of gallium nitride materials, especially their point defects.

"Point defects are of decisive importance for the electrical and optical defects of gallium nitride. We have analysed samples from Amano's laboratory through the positron annihilation methods that reveal crystal defects on the atomic level, in whose use we are world leaders", Tuomisto says.

"It is tremendously inspiring for Aalto students and young researchers to get to hear the experiences of the recent recipient of the world's most respected science award and to have discussions with him. The Finnish public at large will thus get the opportunity to get first-hand information on the scientific research on the possibilities of present LED-based illumination technology", he says.

Hiroshi Amano will hold a lecture in English that is open to the public called "illuminating the world by LEDs” at Aalto University on 19 March in lecture hall B at Otakaari 1, 15.15-16.15. Welcome!

First photo: Hiroshi Amano © Nobel Media AB / Alexander Mahmoud

Second photo: Filip Tuomisto by Anni Hanén