Manipulating topology in tailored artificial graphene nanoribbons*

As immortalized in the quantum corrals of Crommie, Lutz, and Eigler (Science (1993)), the symmetry of electronic surface states can be controlled by adsorbates. Over the past 30 years, progress in atomic manipulation and automation using scanning probes has enabled the synthesis of increasingly more complex structures. This talk will discuss the properties of one such class of structures: artificial graphene ribbons, first synthesized in 2012 (Nature 483, 306–310 (2012)).

Using density functional theory, tight binding,  and extensive experimental validation, I will show how artificial graphene nanoribbons display not only similar electronic properties, but also similar topological properties to their eponymous counterparts. Specifically, their (quasi-) 1D nature enables the emergence of topologically-protected states depending on the connection between two artificial graphene nanoribbons (Phys. Rev. Lett. 119, 076401 (2017)).  I will demonstrate that these topological states can be used to realize a wide array of Hamiltonians.