A bizarre coreless vortex made of two separate half-pieces of magnetism has been discovered in a lithium-based superconductor.
April 29, 2026
Original Paper
Unconventional mixed state in the nematic superconductor LiFeAs
arXiv · 2604.23401
The Takeaway
Magnetic fields usually pass through superconductors in a very specific, orderly lattice of holes called vortices. In this specific material, those holes split apart into strange, separate strands that don't follow the usual rules of physics. This unconventional state was captured using high resolution scanning, revealing a structural arrangement never seen before. It shows that the internal traffic of magnetism in certain metals is much more complex and flexible than we thought. These unique magnetic structures could be used to store information in entirely new types of quantum computers. This discovery reveals a side of magnetism that has been hidden until now.
From the abstract
In the mixed state of type-II bulk superconductors, the magnetic field penetrates in the form of vortices enclosing one magnetic flux quantum: this is the conventional Abrikosov vortex lattice. Here, by using transverse muon-spin spectroscopy, we demonstrate the presence of an unconventional vortex lattice in LiFeAs single crystals. We also show evidence that the new mixed phase consists of stripes of "coreless" vortices, which are bound states of two spatially separated half-quantum vortices.