Reona Esaki

PHYSICIST NAME: Reona Esaki
STUDENT NAME: Angela Mari Peralta

Biography

Reona Esaki also known as Leo Esaki (江崎 玲於奈 Esaki Reona, born March 12, 1925) is a Japanese physicist who shared the Nobel Prize in Physics in 1973 with Ivar Giaever and Brian David Josephson for his discovery of the phenomenon of electron tunneling. He is known for his invention of the Esaki diode, which exploited that phenomenon. This research was done when he was with Tokyo Tsushin Kogyo (now known as Sony). He has also contributed as a pioneer of the semiconductor superlattice while he was with IBM. He was born in Osaka, Japan. Studying physics at the University of Tokyo, he received his B.Sc. in 1947 and his Ph.D. in 1959. Esaki was awarded the Nobel Prize for research had conducted around 1958 regarding electron tunneling in solids. He moved to the United States in 1960 and joined the IBM T. J. Watson Research Center, where he became an IBM Fellow in 1967. His first paper on the semiconductor superlattice was published when he was with IBM. A comment by Esaki in a 1987 number of Current Contents regarding the original paper on superlattices notes. Quantum tunnelling refers to the quantum mechanical phenomenon where a particle "passes through" some sort of barrier which has higher energy than the particle. Classically, this type of event is impossible and observations of quantum tunnelling are part of the body of experimental evidence that backs quantum mechanical theory and the particle-wave duality of matter. Quantum tunnelling is an evanescent wave coupling effect that occurs in the context of quantum mechanics. Other names for this effect are Wave-mechanical tunnelling, Quantum-mechanical tunnelling and the Tunnel effect.

Contributions

The invention of Leo Esaki the tunnel diode or Esaki diode is a type of semiconductor diode which is capable of very fast operation, well into the microwave frequency region, by using quantum mechanical effects. It was invented in August 1957. In 1973 he received the Nobel Prize in Physics, jointly with Brian Josephson, for discovering the electron tunneling effect used in these diodes. These diodes have a heavily doped p–n junction only some 10 nm (100 Å) wide. The heavy doping results in a broken bandgap, where conduction band electron states on the n-side are more or less aligned with valence band hole states on the p-side. Tunnel diodes were manufactured by Sony for the first time in 1957 followed by General Electric and other companies from about 1960, and are still made in low volume today. Tunnel diodes are usually made from germanium, but can also be made in gallium arsenide and silicon materials. They can be used as oscillators, amplifiers, frequency converters and detectors.

Object of Interest

I have chosen Reona “Leo” Esaki because he one of the few known physicists in our continent resembling our nation as Asians. His invention the tunnel diode also caught my attention. With his invention, our gadgets in our world today, he made the the esaki diode to make advance oscillators, amplifiers, detectors and frequency converters and functioning with more fast performance.