Ali Javan

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Ali Javan
علی جوان
Javan ali.jpg
Born (1926-12-26) December 26, 1926 (age 87)
Tehran, Iran
Nationality Iranian American
Fields Physicist
Institutions Columbia
Bell Labs
MIT
Alma mater Columbia
University of Tehran
Doctoral advisor Charles Townes
Doctoral students Michael S. Feld
Known for Gas laser
Notable awards Albert Einstein World Award of Science (1993)

Ali Javan (Persian: علی جوان‎ - ‘Ali Javān, Azerbaijani: Əli Cavan, علی جوان, born December 26, 1926) is an Iranian-American physicist and inventor at MIT. His main contributions to science have been in the fields of quantum physics and spectroscopy. He co-invented the gas laser in 1960, with William R. Bennett.[1] In 2007 Javan was ranked Number 12 on the list of the "Top 100 Living Geniuses".[2]

Life and career[edit]

Ali Javan was born in Tehran to Iranian Azerbaijani parents from Tabriz.[3] He graduated from Alborz High School, started his university studies at University of Tehran and came to the United States in 1948 right after the war. He received his PhD in physics in 1954 from Columbia University under his thesis advisor Charles Townes. In 1955 Javan held a position as a Post Doctoral in the Radiation Laboratory and worked with Townes on the atomic clock research, and used the microwave atom beam spectrometer to study the hyperfine structure of atoms like copper and thalium.

In 1957 he published a paper on the theory of a three-level maser,[4] and his discovery of the stimulated Raman effect that a Stokes-shifted Raman transition can produce amplification without requiring a population inversion.[5][6] The effect was the precursor of a class of effects known as Lasers Without Inversion, or the LWI effect.[7] He joined Bell Telephone Laboratories in 1958 shortly after he conceived the working principle of his gas discharge Helium Neon laser, and subsequently submitted his paper for publication and was reviewed by Samuel Goudsmit in 1960.[8][9]

Javan carried out the first demonstration of optical heterodyne beats in 1961.[10][11] Another major experiment was his observation of the detuning dip called the Lamb dip while scanning the frequency of a single-mode laser across the Doppler-broadened gain profile.[12] In 1964 Javan and Townes devised experiments using lasers to test special relativity including a variant of the Michelson-Morley ether drift experiment to study the anisotropy of space.[13]

At MIT in the early 1960s, Ali Javan started a research project aimed at extending microwave frequency-measuring techniques into the infrared, he then developed the first absolutely accurate measurement of the speed of light.[14]

Javan first worked at Massachusetts Institute of Technology as an associate professor of physics in 1961 and has remained Francis Wright Davis Professor Emeritus of physics since 1964. He continued researching into the area of "optical electronics", which envisions scaling electronic elements in such a way that they would be capable of handling frequencies as high as visible optical radiation frequencies.[15] His contributions to nanophotonics included the introduction of the concept of an optical antenna of several wavelengths long which enables the near-complete confinement of an incident optical field coupled to it, and forming the antenna in nanoscale.

He is married and has two daughters with his wife Marjorie.

The gas laser[edit]

The gas laser was the first continuous-light laser and the first laser to operate "on the principle of converting electrical energy to a laser light output." By definition, "a gas laser is a laser in which an electric current is discharged through a gas to produce light." Ali Javan received U.S. patent #3,149,290 together with William Bennett for the "Gas Optical Maser". Ali Javan first tested his invention on December 12, 1960.

Laser beam transmission[edit]

On December 13, 1960, the first telephone conversation using laser beam transmission occurred. Ali Javan describes the moment: "I put in a call to the lab. One of the team members answered and asked me to hold the line for a moment. Then I heard a voice [Mr. Balik], somewhat quivering in transmission, telling me that it was the laser light speaking to me."[16]

Importance of the gas laser[edit]

The gas laser laid the foundation for fiber optic communication. Laser telecommunication via fiber optics is known to be the key technology used in today's Internet.[17] Helium-Neon gas lasers were the first lasers to be mass-produced. They were used in everything from UPC checkout scanners, video disc players to medical and monitoring technologies and laser printers. Although they have been largely replaced by diode-pumped solid state lasers and laser diodes, they are now used principally for specialized applications such as interferometry and holography due to their long coherence length and Gaussian irradiance profile.

Honors[edit]

See also[edit]

References[edit]

Notes

  1. ^ Taylor, Nick (2000). LASER: The inventor, the Nobel laureate, and the thirty-year patent war. New York: Simon & Schuster. pp. 125–128. ISBN 0-684-83515-0. 
  2. ^ "Top 100 living geniuses" Daily Telegraph (28 October 2007)
  3. ^ "Ali Javan" on the Farhangsara website
  4. ^ Javan, A. Theory of a 3-Level Maser, Physical Review, 1957
  5. ^ Javan, A. Transitions a Plusieurs Quanta Et Amplification Maser Dans Les Systemes a Deux Niveaux, Journal De Physique Et Le Radium, 1958
  6. ^ Ali Javan interviewed by Jeff Hecht, on Feb 28, 1985. Lasers and Applications
  7. ^ MIT Web Page of Ali Javan. Biographical Sketch.
  8. ^ Interview with Ali Javan by Lee Sullivan at the Optical Society of America, Boston, Massachusetts (September 4, 2008)
  9. ^ Javan, Herriott and Bennett, Population Inversion and Continuous Optical Maser Oscillation in a Gas Discharge Containing a He-Ne Mixture, Physical Review Letters, 1961
  10. ^ Interview with Ali Javan by Lee Sullivan at the Optical Society of America, Boston, Massachusetts (September 4, 2008) "[...]with Ed Ballik, the two of us saw the very first experiment done with lasers, a significant experiment showing the color purity of it, heterodyning them [two free running lasers]. The very first paper published by Optical Society is just that. [...]"
  11. ^ Javan, Ballik, Frequency Characteristics of a Continuous-Wave He-Ne Optical Maser, Journal of the Optical Society of America (1962)
  12. ^ Haken, Hermann. Laser Theory, Springer, 1984. pp. 199. ISBN 3540121889
  13. ^ Jaseja, Javan, Murray, Townes, Test of Special Relativity or of Isotropy of Space by Use of Infrared Masers, Physical Review a-General Physics (1964)
  14. ^ Javan, Ali. "Measurement of the Frequency of Light". Annals of the New York Academy of Sciences (February 1969)
  15. ^ Javan, Ali with Blair, Betty. "Scientists Who Made A Difference: Ali Javan, The Gas Laser and Beyond", Azerbaijan International, Vol. 4:2 (Summer 1996), "[...] I'm now working in a new area that I call "Electronics at Optical Frequencies." Computers, for example, use microchips that operate at radio frequencies-MHz (Mega-Hertz) and GHz (Giga-Hertz). I'd like to take electronics out of radio frequency into the light wave frequency range. [...]"
  16. ^ Javan, Ali with Blair, Betty. "Scientists Who Made A Difference:Ali Javan, The Gas Laser and Beyond", Azerbaijan International, Vol. 4:2 (Summer 1996), pp. 14-18
  17. ^ "Iran holds 1st fully domestic laser exhibit" on the Press TV website (February 28, 20120)
  18. ^ "Albert Einstein World Award of Science 1993". Retrieved August 13, 2013. 

Bibliography

External links[edit]