Poster presentation

IETS spectroscopy of finite size two-dimensional valence-bond solids
M. Ferri-Cortés¹ and J. Fernández-Rossier^1,2

1 Departament of Applied Physics, University of Alicante, 03690 Sant Vicent del Raspeig (Spain).
2 Theory of Quantum Nanostructures Group, International Iberian Nanotechnology Laboratory (INL), 4715-330 Braga, Portugal

We model the IETS associated to spin excitation in finite-size spin lattices known to have a Valence Bond Solid state in the limit. Specifically, we consider a cluster of S=3/2 spins interacting with a family of non-linear Heisenberg exchange model that includes both the AKLT limit and the pure-Heisenberg limits. In the neighbourhood of the AKLT point we find gapless edge excitations akin of the edge states of the Haldane spin chains. We also consider a spin ½ model in Kagome-honeycomb lattice that interpolates between the Heisenberg and Valence-bond limit. The realization of these model-systems with nanographenes is briefly discussed.