Abstract

We report the discovery of Mobius, Ring, Figure-8, and Hopf-link Crystals in NbSe3, conventionally grown as ribbons and whiskers. We also reveal their formation mechanisms of which two crucial components are the spherical selenium (Se) droplet, around which a NbSe3 bar wraps due to surface tension, and the monoclinic (P2(1)/m) crystal symmetry inherent in NbSe3, which induces a twist in the strip when bent. Our crystals provide a non-fictitious topological Mobius world governed by a non-trivial real-space topology. We class ed these topological crystals as an intermediary between condensed matter physics and mathematics.

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