Integrated Calendar

We investigate several questions that concern with disorder using three main methods:
A. A controlled expansion in the heat capacity critical exponent.
B. Large N models.
C. AdS/CFT
In the talk I will probably not get to say much about method C., but I will explain methods A. and B.
Method A. can be used to derive concrete results about the disordered 3d Ising model. Method B. can be used to derive a certain generalization of the Imry-Ma result and also it leads to some predictions that can be cross-checked using method C. Using method B. one can also obtain closed form RG flows between pure and disordered fixed points.

Over the past decade, the physics of low dimensional electronic systems has been revolutionized by the discovery of materials with very unusual electronic properties where the behavior of the electrons is governed by the Dirac equation. Among these, graphene has taken center stage due to its ultrarelativistic-like electron dynamics and its potential applications in nanotechnology. Moreover, recent advances in the design and nanofabrication of heterostructures based on van der Waals materials have enabled a new generation of quantum electronic transport experiments in graphene. In this talk I will describe our recent experiments exploring electron-electron interaction driven quantum phenomena in ultra-high quality graphene-based van der Waals heterostructures. In particular I will show two novel realizations of a symmetry-protected topological insulator state, specifically a quantum spin Hall state, characterized by an insulating bulk and conducting counterpropagating spin-polarized states at the system edges. Our experiments establish graphene-based heterostructures as highly tunable systems to study topological properties of condensed matter systems in the regime of strong e-e interactions and I will end my talk with an outlook of some of the exciting directions in the field.