With an intricate structure reminiscent of the deep carvings in the Hagia Sophia, the engineered crystal pictured above may go down in history as one of the wonders of our generation. The amazing structure, based on a mathematical surface known as a “gyroid” was built from crystallized tantalum arsenide using modern manufacturing techniques.
Gyroids do exist in nature, for example in the shimmering rainbows of butterfly wings. But this was one made to order based on calculations predicting that a precisely built gyroid structure, with the symmetries of the surface broken in specific ways, would allow researchers to identify Weyl fermions.
This could change everything
Named after the physicist Herman Weyl, who predicted their existence in 1929, the massless particles are true wonders of nature, in the “this could change everything” vein.Firstly, unlike the Higgs boson (controversially known as the “god particle”), the Weyl particle sticks around. A lot of the particles theorized in the wake of Einstein’s paradigm changing shake up of physics can be seen only by smashing other particles together in super-colliders, disappearing soon after their high-energy birth. But now that scientists have defined the “Weyl photonic crystals” in which the Weyl fermions can be generated, they can make more of them, any time they want.
Second, these Weyl particles are really different from any of the other bits of the universe that we usually catch running around. Ling Lu, MIT-based lead author of one of two studies reporting this month on Weyl fermions, compares them to monopole magnets. Do you remember experimenting with magnets in school? If you cut a magnet in half, you don’t get one ‘south’ bit and one ‘north’ pole — instead you get two new magnets, each with its own north and south poles. The Weyl fermion is crazy weird, like finding a magnet that has only one pole. Plus, they have no mass! Says Zahid Hasan, Princeton-based co-author of a second paper confirming the new particles:
“The physics of the Weyl fermion are so strange, there could be many things that arise from this particle that we’re just not capable of imagining now.”
These strange properties bring us to the third wonder of Weyl particles: they can carry a charge, just like electrons do, but without generating waste heat. You know how the fan is always running or your thighs are getting toasted by your electronic gadgets? All that heat wastes energy. Electronic devices based on Weyl particles could be like LEDs are to the old Edison incandescent lightbulb.
They can also carry a charge long distances, which could revolutionize the power grid, overcoming power transmission obstacles currently faced in the use of small, localized generators instead of big, centralized power plants.
These dreams could take a while, as scientists will have to get to know this new particle before we can harness its amazing abilities. But simpler technologies could develop much sooner: for example large single-mode lasers might be realized first. These would allow ever more precise use of lasers, which are already omnipresent in barcode scanners, disk readers, and a multitude of other modern applications.
The Weyl fermions are so geeky, we are waiting to see if the mainstream media even takes a stab at reporting this breakthrough. We hope you get to be the first to tell your friends you know all about it (which might be a slight exaggeration…if you really want to be a geek god, this will start you surfing — from the Dirac equation through spinons and beyond).