Directly Probing Quantum Hall Physics in Graphene with Tunneling Transistors

Scanning tunneling spectroscopy (STS) is a conventional method used to directly probe the electronic structure and phonon spectrum of graphene and its multilayers. However, STS measurements require extreme mechanical stability, and thus are difficult to incorporate into experimental setups with ultra-high magnetic fields and extremely low temperatures. We report an alternative method that employs tunneling field effect transistors to directly probe the electronic and phononic spectrum of graphene and its multilayers. These transistors are composed of 2D materials that are stacked into ultra-clean heterostructures and can function in magnetic fields and temperatures that are difficult or inaccessible to STS. We will discuss the latest progress towards using these nanodevices to measure and manipulate quantum hall states and phonons in graphene and its multilayers.