Rogue waves of light, rare and explosive flare-ups that are mathematically similar to gigantic and terrifying freak waves at sea, have recently been tamed by a group of researchers.
University of California, Los Angeles' (UCLA) 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.
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 fibres.
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 recognised 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. 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.
Solli and Jalali are developing time-stretching devices that slow down electrical signals; such devices could be used in new optical analogue-to-digital converters 1,000 times faster than current electronic versions, said an UCLA release.
Their findings will be presented during the Optical Fibre Communication Conference and Exposition/National Fiber Optic Engineers Conference (OFC/NFOEC), taking place March 22-26 in San Diego, California.