The Nobel Prize in Physics 2014 has been awarded to Isamu Akasaki, Meijo University, Nagoya, Japan, and Nagoya University, Japan, Hiroshi Amano, Nagoya University, Japan, and Shuji Nakamura, University of California, Santa Barbara, CA, USA, “for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”.
Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura have succeeded where many others had failed. They developed blue LEDs (light emitting diodes) which, together with existing red and green ones, allowed the energy-efficient creation of white light, sounding the death knell for incandescent lighting and contributing to saving important resources.
The material of choice was Gallium nitride – Akasaki and Amano were the first to succeed in creating a high-quality crystal. They presented their first diode emitting blue light in 1992. Nakamura also succeeded in generating high quality GaN crystals, and was able to explain the behavior of the gallium nitride layers developed by Akasaki and Amano. He simplified the process, coming up with a different solution for constructing the electrode.
During the 1990s, both teams further improved their LEDs, making them more efficient and leading to the breakthrough of LED lighting.
Isamu Akasaki, born January 30, 1929 in Chiran, Japan, gained his Ph.D. from Nagoya University, Japan, in 1964. He began working at Matsushita Electric Industrial Co., Ltd., Kadoma, Japan.
Currently, Akasaki is Professor at Meijo University, Nagoya, and Distinguished Professor at Nagoya University, Japan.
Hiroshi Amano, born 1960 in Hamamatsu, Japan, received his Ph.D. from Nagoya University, Japan, in 1989.
Currently, Amano is Professor at Nagoya University, Japan.
Shuji Nakamura, born May 22, 1954 in Ikata, Japan, was awarded a Doctor of Engineering degree from the University of Tokushima, Japan, in 1994. After working for Nichia Corporation, Anan, Japan, he took a position as a professor of engineering at the University of California, Santa Barbara, USA, in 1999.
Publications of Isamu Akasaki
- Origin of defect-insensitive emission probability in In-containing (Al,In,Ga)N alloy semiconductors, Shigefusa F. Chichibu, Akira Uedono, Takeyoshi Onuma, Benjamin A. Haskell, Arpan Chakraborty, Takahiro Koyama, Paul T. Fini, Stacia Keller, Steven P. DenBaars, James S. Speck, Umesh K. Mishra, Shuji Nakamura, Shigeo Yamaguchi, Satoshi Kamiyama, Hiroshi Amano, Isamu Akasaki, Jung Han, Takayuki Sota, Nature Materials 2006, 5, 810–816. DOI: 10.1038/nmat1726
- Cyril Pernot, Myunghee Kim, Shinya Fukahori, Tetsuhiko Inazu, Takehiko Fujita, Yosuke Nagasawa, Akira Hirano, Masamichi Ippommatsu, Motoaki Iwaya, Satoshi Kamiyama, Isamu Akasaki, Hiroshi Amano, Improved Efficiency of 255–280 nm AlGaN-Based Light-Emitting Diodes, Appl. Phys. Express 2010, 3, 061004. DOI: 10.1143/APEX.3.061004
- Breakthroughs in Improving Crystal Quality of GaN and Invention of the p–n Junction Blue-Light-Emitting Diode, Isamu Akasaki, Hiroshi Amano, Jpn. J. Appl. Phys. 2006, 45, 9001. DOI: 10.1143/JJAP.45.9001
- GaInN-Based Solar Cells Using Strained-Layer GaInN/GaInN Superlattice Active Layer on a Freestanding GaN Substrate, Yousuke Kuwahara, Takahiro Fujii, Toru Sugiyama, Daisuke Iida, Yasuhiro Isobe, Yasuharu Fujiyama, Yoshiki Morita, Motoaki Iwaya, Tetsuya Takeuchi, Satoshi Kamiyama, Isamu Akasaki and Hiroshi Amano, Appl. Phys. Express 2011, 4, 021001. DOI: 10.1143/APEX.4.021001
- Masataka Imura, Kiyotaka Nakano, Gou Narita, Naoki Fujimoto, Narihito Okada, Krishnan Balakrishnan, Motoaki Iwaya, Satoshi Kamiyama, Hiroshi Amano, Isamu Akasaki, Tadashi Noro, Takashi Takagi, Akira Bandoh, Epitaxial lateral overgrowth of AlN on trench-patterned AlN layers, J. Crystal Growth 2007, 298, 257–260. DOI: 10.1016/j.jcrysgro.2006.10.043
Publications of Hiroshi Amano
- Guangxu Ju, Yoshihiro Kato, Yoshio Honda, Masao Tabuchi, Yoshikazu Takeda, Hiroshi Amano, X-ray investigations of GaInN single quantum wells grown by atomic layer epitaxy and metalorganic vapor phase epitaxy, Physica Status Solidi C 2014, 11 (3–4), 393–396. DOI: 10.1002/pssc.201300670
- Koji Okuno, Takahide Oshio, Naoki Shibata, Yoshio Honda, Masahito Yamaguchi, Hiroshi Amano, Enhancement of light output power on GaN based light emitting diodes using two direction stripe patterned sapphire substrate, Physica Status Solidi C 2014, 11, 722–725. DOI: 10.1002/pssc.201300470
- Yi Lu, Hiroki Kondo, Kenji Ishikawa, Osamu Oda, KeigoTakeda, Makoto Sekine, Hiroshi Amano, Masaru Hori, Epitaxial growth of GaN by radical-enhanced metalorganic chemical vapor deposition (REMOCVD) in the downflow of a very high frequency (VHF) N2/H2 excited plasma – effect of TMG flow rate and VHF power, J. Crystal Growth 2014, 391, 97–103. DOI: 10.1016/j.jcrysgro.2014.01.014
- Cao Miao, Yoshio Honda, Masahito Yamaguchi and Hiroshi Amano, Growth of InGaN/GaN multiple quantum wells on size-controllable nanopyramid arrays, Jpn. J. Appl. Phys. 2014, 53, 0303060. DOI: 10.7567/JJAP.53.030306
- Guangxu Ju, Yoshio Honda, Masao Tabuchi, Yoshikazu Takeda, and Hiroshi Amano, In situ X-ray investigation of changing barrier growth temperatures on InGaN single quantum wells in metal-organic vapor phase epitaxy, J. Appl. Phys. 2014, 115, 094906. DOI: 10.1063/1.4867640
- H. Amano, T. Kawashima, D. Iida, M. Imura, M. Iwaya, S. Kamiyama, I. Akasaki, Isamu, in Nitrides with Nonpolar Surfaces (Ed. Tanya Paskova), Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, 2008. ISBN: 978-3-527-40768-2
Publications of Shuji Nakamura
- Prospects for LED lighting, Siddha Pimputkar, James S. Speck, Steven P. DenBaars, Shuji Nakamura, Nature Photonics 2009, 3, 180–182. DOI: 10.1038/nphoton.2009.32
- Origin of defect-insensitive emission probability in In-containing (Al, In, Ga) N alloy semiconductors, Shigefusa F. Chichibu, Akira Uedono, Takeyoshi Onuma, Benjamin A. Haskell, Arpan Chakraborty, Takahiro Koyama, Paul T. Fini, Stacia Keller, Steven P. DenBaars, James S. Speck, Umesh K. Mishra, Shuji Nakamura, Shigeo Yamaguchi, Satoshi Kamiyama, Hiroshi Amano, Isamu Akasaki, Jung Han, Takayuki Sota, Nature Mat. 2006, 5, 810–816. DOI: 10.1038/nmat1726
- High Power and High External Efficiency m-Plane InGaN Light Emitting Diodes, Mathew C. Schmidt, Kwang-Choong Kim, Hitoshi Sato, Natalie Fellows, Hisashi Masui, Shuji Nakamura, Steven P. DenBaars and James S. Speck, Jpn. J. Appl. Phys. 2007, 46, L126. DOI: 10.1143/JJAP.46.L126
- Demonstration of Nonpolar m-Plane InGaN/GaN Laser Diodes, Mathew C. Schmidt, Kwang-Choong Kim, Robert M. Farrell, Daniel F. Feezell, Daniel A. Cohen, Makoto Saito, Kenji Fujito1, James S. Speck, Steven P. DenBaars and Shuji Nakamura, Jpn. J. Appl. Phys. 2007, 46, L190. DOI: 10.1143/JJAP.46.L190
- Improved electroluminescence on nonpolar m -plane InGaN/GaN quantum wells LEDs, Kwang-Choong Kim, Mathew C. Schmidt, Hitoshi Sato, Feng Wu, Natalie Fellows, Makoto Saito, Kenji Fujito, James S. Speck, Shuji Nakamura, Steven P. DenBaars, Physica Status Solidi (RRL) – Rapid Research Letters 2007, 1, 125–127. DOI: 10.1002/pssr.200701061