How to blend together photonsS

Scientists have developed a technique to change the color and shape of photons. This could be a boon for quantum computing.

Photons are the term used to describe the packets of energy that fly through the vacuum of space at the speed of light. Although they are discrete packets of energy, they each have a characteristic wavelength associated with them. That wavelength in visible light determines the color, or energy level, of the photon. Although we can't see other photons, they too have certain wavelengths associated with their energy levels.

Photons are basic enough that they don't degrade. They don't change unless acted upon. Generally, the only way to "act upon" it is to let it be absorbed by some substance. That makes a photon into an on-off switch, which is useful, but not as versatile as a dimmer. Scientists have found a way to change the wavelength of photons without absorbing them.

They made a crystal into which two streams of photons were channeled. One was a load of infrared photons of 1300 nanometer wavelengths. The other was a laser beam of 1550 nm photons. The crystal lattice blended and directed the two streams, giving off a stream of 710 nanometer wavelength photons.

With crystals like this, and some careful calculations, the "on-off" nature of computing might be changed. Instead of switching bits on or off, they can be in many different states. Instead of each bit being a part of one calculation, it can be a part of many at the same time. Ideally, all the things a computer now does sequentially, could instead be done mostly simultaneously.

Top Image: Photons in a lattice Via New Scientist and Physical Review Letters.