Weitz Group

Our work is dedicated to understanding the fundamental electronic properties of nanoscopic materials. We especially focus on novel systems such as organic semiconductors and 2-dimensional materials such as graphene. Examples of topics we are interested in are:

Colored SEM image of bilayer graphene (red) suspended between metal contacts (yellow) with suspended top gate (blue) (cf. Science 330, 812 (2010))

Quantum transport in bilayer graphene

Bilayer graphene is a fascinating system, since an applied electric field perpendicular to the layers can control the “which-layer” index. In the quantum-Hall regime, this allows to identify the underlying order of the individual filling factors. Bilayer graphene is not only fascinating at high magnetic fields. For example, we have identified that the ground state of ultraclean bilayer graphene is gapped due to the exchange interaction. Theory predicts several interesting possible ordered ground states that have experimentally not been conclusively identified.

Current density through a mulitlayer MoS2 flake as function of bias voltage (cf. pss (a) 212, 2059 (2015))

Electronic properties of organic semiconductors and transition metal dichalcogenides

We are interested in the intrinsic electronic properties of high-performance organic small molecule and polymer semiconductors. Mostly, we rely on temperature dependent charge transport measurements to identify the electronic properties of such materials. For example, temperature and bias dependent charge transport has allowed us to entangle the contributions of contact and flake resistance of a MoS2 multilayer to the overall transistor performance.

Prof. Thomas Weitz