High resolution X-ray diffraction data on forms I-IV of sulfathiazole and neutron diffraction data on forms II-IV have been collected at 100 K and analyzed using the Atoms in Molecules topological approach. The molecular thermal motion as judged by the anisotropic displacement parameters (adp's) is very similar in all four forms. The adp of the thiazole sulfur atom had the greatest amplitude pe...

A lattice of optical ring resonators can exhibit a topological insulator phase, with the role of spin played by the direction of propagation of light within each ring. Unlike the system studied by Hafezi et al., [Nat. Phys. 7, 907 (2011).] topological protection is achieved without fine-tuning the interresonator couplings, which are given the same periodicity as the underlying lattice. The topo...

We define a fixed point action in two-dimensional lattice CP models. The fixed point action is a classical perfect lattice action, which is expected to show strongly reduced cutoff effects in numerical simulations. Furthermore, the action has scale-invariant instanton solutions, which enables us to define a correct topological charge without topological defects. Using a parametrization of the f...

We define a fixed point action in two-dimensional lattice CP models. The fixed point action is a classical perfect lattice action, which is expected to show strongly reduced cutoff effects in numerical simulations. Furthermore, the action has scale-invariant instanton solutions, which enables us to define a correct topological charge without topological defects. Using a parametrization of the f...