This Photonic Crystal Bends Light Like a Black Hole

One of the first observational tests of unstipulated relativity was that the path of light bends in the presence of mass. Not only refracts the way light changes direction as it enters glass or other transparent materials, but bends withal a curved bath. This effect is inside to a range of physical phenomena, from woebegone holes to gravitational lensing to observations of visionless matter. But considering the effect is so tiny on human scales, we can’t study it hands in the lab. That could transpiration in the future thanks to a new discovery using distorted photonic crystals.

Photonic crystals are materials with a periodic refractive alphabetize on nanometer scales. They occur naturally in things such as opals and the wings of some species of butterflies, which gives them their colorful pearlescent rippling effect. They’ve been known since the 1800s, but in the late 1980s, we began to be worldly-wise to make simple photonic crystals, and research on the materials really started to take off.

Fiber optics and other wide optical materials ushered in the field of photonics, where we can now start to make photonic crystal materials with very specific properties, such as tuning them to be sensitive to specific wavelengths or focusing light increasingly effectively. This new research focuses on a type of material known as distorted photonic crystals.

Bending light with a distorted photonic crystal. Credit: K. Kitamura

Normally you wouldn’t want your crystal to have any distortions. The increasingly resulting you can make your material, the increasingly uniformly light will behave while passing through it. But in this case, the team was worldly-wise to gradually deform the spacing of the crystal lattice. This meant that the periodic refractive alphabetize shifts gradually as you move through the material. For light, this ways the value of refraction gradually varies, just as it does for light passing near a massive soul such as a woebegone hole. The result is that light follows the same kind of curved path as gravitationally lensed light.

The authors undeniability this effect pseudogravity, and it could be used to simulate the effects of unstipulated relativity. You could imagine stuff worldly-wise to create photonic crystals that simulate the lensing effects of galaxies, or plane simulations of a woebegone hole’s event horizon. If we can make distorted crystals with the right properties, we can do all kinds of pseudogravity experiments.

While pseudogravity makes for unconfined headlines, the early uses for distorted photonic crystals will be in optical communications and optical computing. The crystals can deflect light paths without any significant loss of intensity or signal, which will be a powerful tool for things such as ultra-high-speed internet and the next generation of mobile communication.

This ways when we do get virtually to doing pseudogravity experiments, we’ll be worldly-wise to communicate the results with incredible speed and efficiency.

Reference: Nanjyo, Kanji, et al. “Deflection of electromagnetic waves by pseudogravity in distorted photonic crystals.” Physical Review A 108.3 (2023): 033522.