Spin chains on metallic surfaces: Model systems for heavy fermion quantum criticality

Cobalt adatoms on metallic surfaces can be described by a simple model: a spin 3/2 Heisenberg chain with single ion anisotropy, coupled antiferromagnetically to the two dimensional conduction elections. On the basis of numerical simulations and scaling arguments we will show that this simple system allows us to explore a wealth of quantum phenomena – including the breakdown of quasiparticles, dissipation-induced quantum phase transitions, topological phases with protected edge modes, and Kondo-screened heavy Fermi liquid phases.