We are seeking two talented and highly motivated PhD candidates for a new experimental project in quantum electronics and nanomechanics. The project uses the outstanding force-sensing properties of carbon nanotubes to study quantum physics in regimes that have not yet been accessed experimentally. One project focuses on measuring the effects of quantum superposition in an electromechanical circuit. The particle under test will be a vibrating carbon nanotube, consisting of approximately one million nucleons. To study its quantum behaviour, you will incorporate it first into a superconducting junction, and then into a superconducting qubit. The ultimate aim is to realise a new kind of matter-wave interferometer, in which the wavefunction of the entire nanotube is separated, recombined, and measured. This would dramatically push the boundary of quantum superposition from the realm of molecules towards the realm of fabricated objects. The second experiment will study one of the most fascinating known manifestations of collective quantum behaviour, namely superfluidity in helium. There is at present no experimental tool to measure superfluids on the mesoscopic scale, i.e. between the size of atoms and the superfluid coherence length. A vibrating nanotube, working as a tiny moving-wire viscometer, can measure superfluidity on this tiny scale. You will measure viscous damping first in the well-understood superfluid helium-4, and then in its exotic cousin helium-3, whose emergent behaviour mimics fundamental properties of our universe.