2001Advanced TechnologyElectronics
Izuo Hayashi photo

Izuo Hayashi

  • Japan / 1922-2005
  • Physicist
  • Member, The Engineering Academy of Japan

A Pioneering Step in the Development of Optoelectronics through Success in Continuous Operation of Semiconductor Lasers at Room Temperature

Dr. Alferov, Dr. Hayashi and Dr. Panish have made pioneering contributions to the development of optoelectronics as we know it today with the achievement of continuous wave operation of semiconductor lasers at room temperature. They have thus paved the way for commercial use of electronic devices that play an essential role in the building of information infrastructures supporting the worldwide IT revolution.


Brief Biography

Born in Tokyo, Japan
M.S., Physics Department, the University of Tokyo
Associate Professor, the Institute for Nuclear Study, the University of Tokyo
Ph.D. in Science, the University of Tokyo
Researcher, MIT
Member of Technical Staff, Bell Telephone Laboratories (now Bell Laboratories)
Fellow, NEC
Head Scientist, Optoelectronics Joint Research Laboratories
Director, Optoelectronics Technology Research Laboratory, Tsukuba
Advisor, the same Laboratory
Retired from the same Laboratory

Selected Awards and Honors

Fujiwara Prize, Japan
Prize from Institute of Electronics and Communication Engineers, Japan
IEEE Fellow
GaAs Simposium Award
IEEE Electron Device Award (J. J. Ebers)
Asahi Prize, Japan
C&C Prize (with Panish), Japan
IEEE David Sarnoff Award
The Marconi International Award, U. S. A.
Applied Physics Society Prize, Japan

Major Works


Effect of Band Shapes on Carrier Distribution at High Temperature. IEEE J. Quantum Electronics QE-4 (4)., 1968


A Low Threshold Room-Temperature Injection Laser. IEEE J. Quantum Electron, QE-5 (4). (with M. B. Panish and P. W. Foy), 1969


Double Heterostructure Injection Lasers with Room-Temperature Thresholds as low as 2300 A/cm². Appl. Phys. Lett. 16 (8). (with M. B. Panish and S. Sumski), 1970


Junction Lasers Which Operate Continuously at Room-Temperature. Appl. Phys. Lett. 17 (3). (with M. B. Panish and others), 1970


GaAs-AlGaAs Double Heterostructure Injection Lasers. J. Appl. Phys. 42 (5). (with M. B. Panish and F. K. Reinhart), 1971


A Pioneering Step in the Development of Optoelectronics through Success in Continuous Operation of Semiconductor Lasers at Room Temperature

In 1970, Dr. Zh. I. Alferov, Dr. I. Hayashi and Dr. M. B. Panish achieved continuous operation of semiconductor lasers at room temperature, an operation which theretofore had been extremely difficult. Their feat paved the way for the practical uses of semiconductor lasers, a pioneering contribution to the development of the optoelectronics that are an essential component of the information infrastructures that underpin the worldwide IT revolution.

The first semiconductor laser, accomplished in liquid nitrogen in 1962, utilized a homojunction based upon a GaAs layer. However, its requirement of threshold current density, the minimum density necessary for lasing operation, was extremely high, thus permitting pulse operation only and hindering the industrial application of these semiconductor lasers. A variety of subsequent attempts were made to confine light output in an optical waveguide using striped electrodes or a heterostructure of AlGaAs and GaAs layers, but numerous technical bottlenecks yet prevented continuous operation at room temperature. A breakthrough occurred in 1970, when Dr. Alferov in Russia (formerly the Soviet Union), and Drs. Hayashi and Panish in the United States, almost simultaneously succeeded in achieving the continuous operation of semiconductor lasers. The semiconductor lasers they developed are characterized by the fact that they substantially reduced the threshold current density through the application of a double heterostructure consisting of a GaAs active layer, a thin film for radiating light, sandwiched between two AlGaAs layers.

This epoch-making development provided the basis for several subsequent research efforts and paved the way for the practical application of semiconductor lasers. These lasers were then applied to a number of new technologies, accelerating the development of the optoelectronics field that has given birth to a revolution in industrial and social structures worldwide.

Today, semiconductor lasers can be found not only in the optical fiber communications that connect us to the world via the Internet, the major driving force in the realization of the information society, but also in optical recording technologies such as compact disc players and video disc players, information processing components such as computer memory and laser printers, and media resources such as digital publications.

The continuous operation of semiconductor lasers at room temperature, attained by the three scientists using an AlGaAs double heterostructure, gave birth to an entire class of innovative technical developments. It is no exaggeration that the prosperity of the optoelectronics field as we know it today would not have been possible without their groundbreaking achievement.

For these reasons, the Inamori Foundation is pleased to bestow upon Dr. Alferov, Dr. Hayashi and Dr. Panish the 2001 Kyoto Prize in Advanced Technology.


Abstract of the Lecture

Half Century’s Journey in Research: Applying Physics for the Benefit of Society

I was born in Tokyo in 1922, the fourth son of a scientist of basic medicine. I don’t know why, but it seems like I was a born scientist. As a boy, I would enjoy listening to my father’s stories about science, and some of them still live fresh in my memory. I spent my elementary through high school days at Gakushuin. By the time I made it to the Faculty of Science of the University of Tokyo, World War II was in its closing days, and I had an opportunity to learn about microwaves as I measured the radar of the US Air Force during an air raid. This was the beginning of my life – long research into light.

Over the fifty years since then, I have moved my work from one research institute to another, in Japan and overseas, almost every ten years. My first 20 year career as a researcher was at the University of Tokyo’s laboratory on atomic nuclei, where I was assigned to work on large cyclotron oscillators that employed the same principle as the microwave. While engaged in the development of electronics for measurement there, I developed a growing interest in seeing with my own eyes the electronics being developed in the United States, which at that time was the world leader. I decided to go to the States, a journey that, in retrospect, signaled a great leap in my career. Following my work at two other institutions, I had the privilege of getting to know Mr. John Galt, then head of the research arm of Bell Laboratories, and in 1966 he asked me if I would be interested in doing semiconductor laser research. This unexpected offer raised the curtain on the latter half of my career. I quit my position at the University of Tokyo to become a regular researcher at Bell Laboratories.

Heartened by Mr. Galt’s remark that if semiconductor lasers could operate continuously at room temperature – a feat theretofore believed impossible – it would have a considerable impact on communications technology, I began working in conjunction with Dr. Morton B. Panish. As we groped about together in the dark, I happened upon an ideal hetero junction in a crystal that Dr. Panish had created. This was to pave the way to achieving the continuous operation of semiconductor lasers at room temperature on June 1, 1970.

With this accomplished, I decided to return home to assume a position as a fellow at NEC Laboratories, where I plunged into practical uses for lasers. Sheer devotion on the part of young determined researchers led to a solution to what had once seemed a blind – alley pursuit. In the 1970s, these long – term efforts culminated in the development of many types of equipment employing applied optics, ranging from optical communications to compact disc players. And advances in the application of optics are far from having run their course: the most promising still lie in the future, which I believe will take the form of complex equipment that marries optics with electrons.

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Semiconductor Laser - Continuous Operation and Progress for the Future -

Monday, November 12, 2001
Kyoto International Conference Center
Coordinator & Moderator
Kenichi Iga, Member of the Kyoto Prize Screening Committee; Executive Director, Japan Society for the Promotion of Science
Inamori Foundation
Kyoto Prefectural Government, Kyoto City Government, NHK
With the cooperation
IEICE/Electronic Society, The Japan Society of Applied Physics, IEEE/LEOS Japan Chapter, Optoelectronic Industry and Technology Development Association, Japan Society for the Promotion of Science


Opening Kenichi Iga
Address Toyomi Inamori, Managing Director, The Inamori Foundation
Address Yasuharu Suematsu, Chairman of the Kyoto Prize Committee; Director General, National Institute of Informatics
Laureate Lecture Izuo Hayashi - Laureate in Advanced Technology
"Succeeding in CW Oscillation of Semiconductor Lasers and Overcoming the Difficulties in Realization of Its Practical Usage"
Laureate Lecture Morton B. Panish - Laureate in Advanced Technology
"X - Ray Characterization of Superlattices, and Devices Exploiting Intersubband Transitions in Quantum Wells"
Laureate Lecture Zhores Ivanovich Alferov - Laureate in Advanced Technology
"Double Heterostructure Lasers: Past, Present and Future"
Panel Discussion Co - Moderators:
Michiharu Nakamura, Chairman of the Kyoto Prize Screening Committee; Corporate Officer, President, Research and Development Group, Hitachi, Ltd.
Kenichi Iga
Zhores Ivanovich Alferov
Izuo Hayashi
Morton B. Panish
Yasuharu Suematsu
Isamu Akasaki, Professor, High-Tech Research Center, Meijo University
Tetsuhiko Ikegami, Member of the Kyoto Prize Committee; President, the University of Aizu
Closing Kenichi Iga