  In nature, most materials are composed of atoms with periodic structures.
Hence, it's impossible to introduce topological structures into their lattice
compose, because the atoms as basic blocks cannot be modulated. However, the
lattice compose of metamaterials can be designed conveniently. In our work, we
propose to introduce topological non-trivial structures, Mobius unknots, as the
basic block (the artificial chiral "atoms") to design metamaterials. A 5.95 GHz
intrinsic peak, in addition to the electrical resonance peak near 11 GHz on the
transmission coefficient spectrum was confirmed by theoretical calculations,
finite-difference time-domain (FDTD) simulations and experiments when
electromagnetic waves transfer to a chiral Mobius unknot. Theoretical analysis
indicates that this intrinsic peak originates from the phase transition caused
by the electromagnetic waves propagate along the Mobius unknot non-trivial
structure. It is similar to the state of spin-splitting of electron levels.
Take the artificial chiral "atoms" - Mobius unknots as the basic block, we can
construct two-dimensional and even three-dimensional ordered metamaterials. The
simulation and experimental results showed that the response to electromagnetic
wave in the GHz band can be modulated by the coupling between the periodic
potential and the spin-like of energy levels.
