New imaging technology shows laser pulses are formed from chaos

March 9 (UPI) -- New imaging technology shows laser pulses are formed from chaos.

Lasers, invented in the 1960s, have become a mainstay of science and technology, but surprisingly, scientists still don't entirely understand the laser pulse formation process.

"The reason why understanding these lasers has been so difficult is because the pulses they produce are typically of picosecond duration or shorter," Goëry Genty, a photonics researcher at the Tampere University of Technology in Finland, said in a news release. "Following the complex build-up dynamics of such short pulses for the hundreds, sometimes thousands, of bursts before the laser actually stabilizes has been beyond the capability of optical measurement techniques."

New imaging technology developed by Genty and his colleagues enable scientists to, for the first time, record the temporal and spectral properties of laser pulses at sub-picosecond resolution. Researchers used a computer algorithm to analyze the data and reveal the characteristics of the electromagnetic forces responsible for the laser pulse formation.

Scientists shared their findings this week in the journal Nature Photonics.

"The results provide a very convenient laboratory example of what is known as a 'dissipative soliton system' which is a central concept in nonlinear science and also relevant to studies in other fields, such as biology, medicine and possibly even social sciences," said John. M. Dudley, a researcher at the University of Bourgogne-Franche-Comté.

Analysis of the evolving electromagnetic field during the laser pulse formation revealed self-organizing, wave-like structures, or solitons, forming out of a variety of seemingly random interactions -- from chaos, or noise.

"The results provide a completely new window on previously unseen interactions between emerging dissipative solitons in form of collisions, merging or collapse," Genty said.