Willke, P. et al. Nano Lett. 15, 5110−5115 (2015)

Controllably doping semiconductors to precisely modulate the local charge carrier density is crucial for electronic applications such as field-effect transistors and a broad range of signal detectors. The performance of these electronic devices is significantly influenced by the mobility of charge carriers in these semiconductor systems and there is a strong urge for investigating beyond-Si electronics to retain Moore’s law. Therefore, the aim of this thesis is to controllably dope mono- and bilayer graphene with nitrogen and boron via low-energy ion beam implantation. Furthermore, the defect concentration should be characterized and the impact of different doping levels on carrier mobilities should be investigated.

For more information ask Dr. Martin Statz (martin.statz@uni-goettingen.de).

How do electrons interact with one another in ultra-clean graphene and its multialyers? Which novel quantum phases can appear? To answer these fundamental questions we engineer graphene layers that hang freely like a bridge in vacuum (typical sample layout see image on right) and measure their electrical properties at cryogenic temperatures. One example of a quantum phase we recently have discovered is detailed here: Geisenhof et al. Nature 598, 53-58 (2021)

Metal organic frameworks (MOFs) can be composed of chosen dedicated building blocks. This includes the tuning of band gaps and the possibility to introduce magnetic centers. In this thesis we aim to explore nanoscale charge transport in novel MOFs at cryogenic and room temperature.

We are interested in influencing charge transport in graphene via the proximity of graphene to other two dimensional materials (e.g. MoS2). The goal of the thesis is to investigate the properties of such new hybrid devices in electric and magnetic fields and understand which of the characteristics of the initial materials dominates in the hybrid device.