Harvard scientists invent chip that squeezes light to bring super-fast quantum computers closer

Physicists from Harvard University have succeeded in creating a new type of optical chip that is able to control light so that it flows infinitely faster than the speed of light, which could eventually pave the way for superfast light-based quantum computers.

According to Einstein's theory of special relativity, nothing can travel faster than the speed of light in a vacuum, and as such, light speed is considered to be the universal speed limit of everything. However, if we want to have quantum computers, we will have to somehow make it possible for information to move at speeds that are faster than the speed of light.

In 2013, a group of scientists from Vanderbilt University and the Oak Ridge National Laboratory in Tennessee, US created a new class of metamaterials that have a refraction index of zero. This material is peculiar as it has a phase velocity of light that is infinite, which basically means that when light strikes the material, the crest of the light waves move at a speed that is infinitely fast.

Essentially, although it sounds really confusing, this is possible because the light itself isn't travelling faster than the speed of light, and the crests of the waves are oscillating through time, not space.

Manipulating photons just like electrons

Harvard's scientists were intrigued by this material and decided to see if they could put it on to a chip, and they found that the peculiar conditions of the metamaterial made it easy for photons to be treated the same way we currently manipulate electrons, so it was possible to squeeze the photons down to the microscopic scale and then turn them around.

Their research, entitled "On-chip zero-index metamaterials" is published in the journal Nature Photonics.

"Usually, light needs to be handled very carefully and squeezed very slowly. With our material, you relax those constraints completely. You can bend the light, squeeze it, twist it," Eric Mazur, Balkanski professor of physics and applied physics at Harvard University and area dean of applied physics, who led the study, told Quartz.

There are a myriad of commercial uses for this metamaterial, Mazur stressed, such as in telecommunications, which make use of electromagnetic waves.

Superfast phones and computers that use less battery life

"These waves are everywhere. We can talk on mobile phones because, in our phones, there are electrons that move up and down to create a wave," he said.

"This wave travels to the antennae of the phone company and makes electrons there move up and down, which can be detected and turned into electrical signals that can be turned into an audio signal."

Although there are still several obstacles to address before light-based computers are possible, optical chips fitted with this metamaterial could one day make it possible for smartphones and computers to process information millions of times faster than today.

Battery life would also probably be longer as light tends to conserve energy much better than electrons, which waste energy by creating heat.