Nobel Prize for Physics 2014
The Royal Swedish Academy of Sciences announced its decision to award the Nobel Prize for Physics to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura “for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”.
Isamu Akasaki is a Japanese citizen. He was born 1929 in Chiran, Japan and educated in Japan. He is currently a Professor at Meijo University, Nagoya, and Distinguished Professor at Nagoya University, Japan.
Hiroshi Amano is a Japanese citizen. He was born in 1960 in Hamamatsu, Japan and educated in Japan. He is a Professor at Nagoya University in Japan.
Shuji Nakamura is an American citizen. He was born in 1954 in Ikata, Japan and educated in Japan. He is currently a Professor at University of California in USA.
Discovery of blue LEDs
The three scientists of Japanese origin have been awarded the Nobel for inventing blue light emitting diodes or LEDs.
Although red and green LEDs have been in existence for decades now, development of blue LEDs posed a formidable challenge to scientists and researchers.
Within a LED, current is applied to multiple semiconductor materials, which emit a particular wavelength of light depending on the chemical make-up of the semiconductor materials in question. Gallium nitride was the semiconductor used by the Japanese researchers to develop the blue LED. Growing adequately big crystal of gallium nitride was the challenge that many researchers couldn’t figure out. Akasaki and Amano, worked together in 1986 to get the gallium nitride to grow to a big size, with the help of a specifically designed scaffold partially made from sapphire.
In 1990, Nakamura also managed to induce the gallium nitride to grow to a big size by manipulating the temperature to induce its growth.
Their work in discovering blue LEDs led to the combining of red, green and blue LEDs to form white LEDs.
Significance of blue LEDs
Blue LED is an extremely significant development on its own, and because it was a stepping stone in the development of white LED, it is a path-breaking milestone.
Blue LEDs are used in many products nowadays. Smartphones, for example, use blue LEDs. White LEDs are used in a plethora of products from lamps tto television screen to computer screens.
LEDs use much less energy than incandescent lamps, and are efficient enough to run on locally generated solar power. It is major development in the 21st century where energy conservation has become vital