A freak wave at sea is a terrifying sight. Seven stories tall, wildly unpredictable, and incredibly destructive, such waves have been known to emerge from calm waters and swallow ships whole.
But rogue waves of light -- rare and explosive flare-ups that are mathematically similar to their oceanic counterparts -- have recently been tamed by a group of researchers at the University of California, Los Angeles (UCLA).
UCLA's Daniel Solli, Claus Ropers, and Bahram Jalali are putting rogue light waves to work in order to produce brighter, more stable white light sources, a breakthrough in optics that may pave the way for better clocks, faster cameras, and more powerful radar and communications technologies. Their findings will be presented during the Optical Fiber Communication Conference and Exposition/National Fiber Optic Engineers Conference (OFC/NFOEC), taking place March 22-26 in San Diego.
Rogue bursts of light were first spotted a year ago during the generation of a special kind of radiation called supercontinuum (SC). SC light is created by shooting laser pulses into crystals and optical fibers. Like the incandescent bulb in a lamp, it shines with a white light that spans an extremely broad spectrum. But unlike a bulb's soft diffuse glow, SC light maintains the brightness and directionality of a laser beam. This makes it suitable for a wide variety of applications -- a fact recognized by the 2005 Nobel Prize in Physics, awarded in part to scientists who used SC light to measure atomic transitions with extraordinary accuracy.
Despite more than 40 years of research, SC light has proven to be difficult to control and prone to instability. Though rogue waves are not the cause of this instability, the UCLA researchers suspected that a better understanding of how noise in SC light triggers rogue waves could improve their control of this bright white light. Rogue waves occur randomly in SC light and are so short-lived that the team had to employ a new technique just to spot them. Although they are rare, they are more common than would be predicted by a bell curve distribution, governed instead by the same "L-shaped" statistics that describe other extreme events like volcanic eruptions and stock market crashes.
By tinkering with the initial laser pulses used to create SC light, Solli and his team discovered how to reproduce the rogue waves, harness them, and put them to work. His results, to be presented at OFC/NFOEC 2009, demonstrate that a weak burst of light, broadcast at the perfect "tickle spot," produces a rogue wave on demand. Instead of disrupting things, it stabilizes SC light, reducing fluctuations by at least 90 percent. The seed wave also decreases the amount of energy needed to produce a supercontinuum by 25 percent. The process, says Solli, is similar to boiling water. "If you heat pure water, it can boil suddenly and explosively," he says. "But normal water has nucleation sites for bubble formation that -- like our seed waves stimulate the supercontinuum -- help the water boil smoothly with less heat."
This new-and-improved white light, funded by DARPA, could help to push forward a range of technologies. Solli and Jalali are developing time-stretching devices that slow down electrical signals; such devices could be used in new optical analog-to-digital converters 1,000 times faster than current electronic versions. These converters could help to overcome the current conversion-rate bottleneck that holds back advanced radar and communication technologies. Stabilized SC light could also be used to create super-fast cameras for laboratory use or incorporated into optical clockworks.
Colleen Morrison | EurekAlert!
Further reports about: > 'rogue' laser waves > Fiber Optic Cables > L-shaped statistics > OFC/NFOEC > Optical Fiber Communication > UCLA > boiling water > calm waters > communications technologies > crystals and optical fibers > laser pulses > light source > optical communication > swallow ships whole > tickle spot > white light
Applicability of dynamic facilitation theory to binary hard disk systems
08.12.2016 | Nagoya Institute of Technology
Will Earth still exist 5 billion years from now?
08.12.2016 | KU Leuven
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
08.12.2016 | Life Sciences
08.12.2016 | Physics and Astronomy
08.12.2016 | Materials Sciences