SEMINAR - Engineering quantum transport in low dimensional electron systems

Abstract : When electron systems are constrained to low dimensions, interactions can lead to exciting many body physics and broken symmetry states, exhibiting topological order and emergent behavior. In the present talk, I will discuss electron transport in nanoscale structures consisting of two dimensional (2D) layered materials as well as one dimensional metallic nanowires. Firstly, I will discuss our efforts to engineer spin-orbit effects in graphene. This was spurred by recent theoretical predictions that heavy metal adatoms such as Indium can introduce spin-orbit coupling in graphene and lead to topological states of matter. In the second part of the talk, I will discuss our ongoing efforts in understanding electron tunneling in Van der Waals heterostructures. We employ atomically thin layers of hexagonal boron nitride as the insulating layer and metals or graphite/graphene as the counter-electrodes. Our results show strong evidence for phonon and defect mediated tunneling in such heterostructures. I will also briefly describe some of our earlier experiments on transport in ultrathin gold nanowires. We observe tunability between a non-Fermi Luttinger liquid state and a disordered state exhibiting hopping transport. In the end, I will present how these efforts can be expanded to create heterostructures of 1D and 2D materials to further explore spintronics, straintronics, tunneling and spin-orbit interactions among other phenomena.

Event Date : 2016-02-15