The Shanghai Institute of Optics and Fine Mechanics under the Chinese Academy of Sciences has found a way to build a compact version of a free-electron laser. But they use a fine wire 8cm wire to emit laser-like light in a broad range of wavelengths funlike typical laser light that is restricted to a narrow range.
Normally such lasers need bulky, high-powered devices housed in large, expensive facilities.
Study co-author Ye Tian told the Shanghai Observer news that the team found a way to sync electrons “like a team of honour guards”, to generate greater power.
“Imagine the electrons as athletes rowing a boat. The team that can make bigger waves and generate higher power will win the race. The best strategy is for all athletes to paddle in the same direction.”
In the study, the Chinese scientists excited free electrons – energetic electrons not bound to matter – by irradiating an iron wire using a high-power ultra-fast laser pulse. The short pulse accelerated the electrons to a high velocity down the wire, which made other electrons in the wire emit electromagnetic waves, with which the free-electron pulse interacted. The electrons then transferred energy to the waves and amplified them.
David Gozzard, with the International Centre for Radio Astronomy Research in Australia said it had a potential application in silicon.
“The more types of devices we can engineer from silicon, the smaller and cheaper we can make a huge variety of sensors and tools. With further refinement, and finding ways to produce higher frequency [visible] light, tiny silicon-based lasers made from this technology will find their way into phones and other devices for high-speed communications and precision sensors.”