I will discuss two domains of condensed matter physics elucidated by new tools: thermal motion in nanomechanical structures and mesoscopic transport of Dirac electrons. By picking up individual carbon nanotubes and coupling them with electrostatic gates and optical cavities, we directly read-out non-equilibrium dynamics and observe real-time Brownian motion. We reveal surprising spectral dynamics obscured by existing measurement techniques, shedding light on the physics behind the unexpectedly low quality-factor in room temperature carbon nanotube resonators. In the second part of this seminar, I will explain how we control the flow of electrons in graphene. Drawing from intuitions in ballistic transport and light optics, we produce collimated electron beams to quantitatively study angularly dependent phenomena such as Klein tunneling, and elucidate how electrons start to behave like a fluid as they interact more strongly with each other. Using scanning gate microscopy, we image how electrons in graphene and hexagonal boron nitride heterostructures follow non-circular cyclotron orbits under the influence of a magnetic field.
Watch a video of the talk here.