A group of physicists demonstrated that waves consisting of groups of photons could travel more quickly than light. The laser technology benefited from the research published in Physical Review Letters.

Laser  Light Research
(Photo: WikiImages/Pixabay)
Laser Light Research


Adjusting the Speed of Light

Researchers have been determining the maximal speed of light pulses for some time. They can be sped up or slowed down until they are practically at a standstill using various materials, such as refractive crystals, optical fibers, and cold atomic gases.

The good news is that scientists from Lawrence Livermore National Laboratory in California and the University of Rochester in New York successfully adjusted the speed of light waves within plasma last year. Fine-tuned waves range from about one-tenth of the usual vacuum speed of light to more than 30% faster.

It's crucial to remember that changing the speed of light won't necessarily send humans back in time. The modification stays within the bounds of physics.

Physics Behind the Speed of Light Tweak

Electromagnetism, the interaction of electrical and magnetic fields, keeps a photon's speed constant. There is no denying that low-frequency photon pulses bump against each other in ways that produce periodic waves.

Group velocity may move more slowly or quickly depending on the electromagnetic characteristics of its surroundings. Group velocity is the rhythmic rise and fall of entire groups of light waves as they flow through matter.

By using a laser to remove electrons from a stream of hydrogen and helium ions, the researchers could slow down or streamline the delivery of light pulses. It changes the group velocity of the light pulses sent through them and compels the characteristics of the pulse to change shape.

Refraction from the plasma fields and the polarized light from the main laser used to break them down were responsible for the overall effect. Even when the collective dance seemed to quicken, the individual light waves moved at their usual speed.

The experiment provides more information about the physics of plasmas and imposes new restrictions on the precision of current models based on theoretical points of view.

On a practical note, the experiment adds more depth to the physics of plasmas and places more constraints on how accurate previous models may be, which is great news for cutting-edge technologies awaiting ideas on how to get around obstacles preventing their implementation.

ALSO READ: Researchers Have Just Developed the Sharpest Laser in the World


A Laser and a Stream of Plasma

The biggest winners in this scenario would be lasers, particularly powerful ones. The solid-state optical components used in conventional lasers are vulnerable to damage as the energy levels increase. According to Made How, a solid state laser employs a crystal with securely bonded atoms. After receiving light from a lamp or another laser, the crystal emits laser light. Two mirrors make up the simplest cavity, one completely reflecting, and the other reflects between 50% and 99% of light.

Yet, through the new study, streams of plasma might be used to alter the properties of light to remedy this issue, but in order to take full advantage of this possibility, we must model the electromagnetic characteristics of the plasma.

It is no accident that Lawrence Livermore National Laboratory, home to some of the most special laser equipment in the world, is eager to comprehend the optical nature of plasmas. We need ever-more powerful lasers for various purposes, like speeding up particle accelerators and developing clean fusion technologies.

RELATED ARTICLE: Learning Optics: What's the Relation Between Laser, Light, and Lenses?

Check out more news and information on Technology in Science Times.