Thursday, June 30, 2011

Celebrating the 50th Anniversary of Nonlinear Optics

During NLO 2011 there will be a symposium celebrating the 50th anniversary of nonlinear optics.

I don’t want to emphasize the well-known speckle which was removed from the famous paper in Physical Review Letters by P. Franken, et al., demonstrating nonlinear optical effects for the first time appeared in 1961. I do want to pay tribute to the great scientist Raman here.

Let us start with a question: When Raman observed Raman scattering in 1928, there was no laser. What was his light source?

(I wish I had prizes for correct answers!)

The answer----“The apparatus used by Raman for the discovery consisted of a
mirror for deflecting sunlight, a condensing lens, a pair of complementary glass filters,
a flask containing benzene and a pocket spectroscope. the total cost not exceeding $25 ” [1]

Raman observed not only the Stokes radiation, which has the lower photon energy than the incident photon, but the extremely weak anti-Stokes radiation.

Below are a few notable things that I know about the symposium invited speaker:

Plenary session speaker Steve Harris discovered optical parametric fluorescence (Wonder why it is called parametric oscillator? ). What less known is that he is inventor the acousto-optic tunable filter. He filed the patent “Tunable acousto-optic method and apparatus” in 1970. Now one type of pulse shaper--Dazzler made by FastLite in France--is based upon this. Whenever we disucussed the acousto-optic tunable filter, my thesis advisor, who was Professor Harris’s graduate student, always made sure the audience know about this history and gave Professor Harris the credit.

Professor Bloembergen, who was awarded a Nobel Prize for his contributions to the field of nonlinear optics and to the development of laser spectroscopy in 1981, will give a talk on the birth of nonlinear optics. I look forward to that talk.

Robert Byer probably will speak about the history of the nonlinear optics. I had a glimpse of his talk from his website, which shows a lot of pictures and fascinating stories. For example, he has a funny picture about “Who Invented This Crazy Idea (of laser driven fusion), Anyway? ” By the end of the 85-page-pdf-talk file there is a picture of Surfing Ocean Waves at Poipu Beach, Kauai. The video is great. I know it will be event better to hear the talk in person!

Algis Piskarskas, the Head of Department of Quantum Electronics and Laser Research Centre at Vilnius University, serves as the one of the advisory board member of the Virtual Institute for Nonlinear Optics (VINO, where they promote open sharing of know how, infrastructures and resources. They have a logo which is a beautiful picture of conical waves:

Gérard Mourou, the inventor of the chirped pulse amplification and the famous book Quantum electronics author Amnon Yariv are also among the invited speakers.

Inspired by another principle of VINO: wider concept and visualization based on the search for truth and beauty in the world that surrounds us, I would like to show a picture that I took during my experiment but have not published.

Above, three sets of sidebands generated in a 160 micro meter fused silica with a pair of fs IR pump lasers.

Without lasers, or without nonlinear optics, we will never see this beauty.

If time allows I will write a follow up blog after I hear talks from the invited speakers.

If you have any comments, please email me at

[1] R. S. Krishnan and R. K. Shankar, Journal of Raman Spectroscopy 10(1), 1