Giant Phonon-induced Conductance in Scanning Tunneling Spectroscopy of Gate-tunable Graphene

The honeycomb lattice of graphene is a unique two-dimensional (2D) system where the quantum mechanics of electrons is equivalent to that of relativistic Dirac fermions. Novel nanometer-scale behavior in this material, including electronic scattering, spin-based phenomena, and collective excitations, is predicted to be sensitive to charge carrier density. In order to probe local, carrier-density dependent properties in graphene we have performed atomically-resolved scanning tunneling spectroscopy measurements on mechanically cleaved graphene flake devices equipped with tunable back-gate electrodes. We observe an unexpected gap-like feature in the graphene tunneling spectrum which remains pinned to the Fermi level (E_F) regardless of graphene electron density. This gap is found to arise from a suppression of electronic tunneling to graphene states near E_F and a simultaneous giant enhancement of electronic tunneling at higher energies due to a phonon-mediated inelastic channel. Phonons thus act as a "floodgate" that controls the flow of tunneling electrons in graphene. This work reveals important new tunneling processes in gate-tunable graphitic layers

Im/mediations:9x9x9

Im/mediations: 9x9x9 is a series of 9 livestream performances – featuring 9 soloists – fragmented and reconfigured in closeup from 9 unique perspectives. Each livestream is a kinetic portrait – a 90-minute exposure, in which movement pushes at the seams of stillness.Each livestream spans 90-minutes, during which the soloist performs a minimalist score of sustained stillness, punctuated by abrupt gestural shifts. Within each stretch of stillness, the closeup framings from 9 simultaneous angles reveal micro-movements beyond the performer’s control. Throughout, the performer engages in a practice called “Interstitial Listening“, aligning each inhale, exhale, and gesture with the dynamic temporality of an irregular metronome, negotiating gaps between the timing of their action and intention.The 9 livestream performances took place from November 1-17, 2022. The virtual audience was invited to arrive and depart anytime throughout each livestream, and to return for multiple streams over the course of 3 weeks.Overall, the 9 livestreams, filmed from 9 simultaneous angles, generated 81 full-HD videos. Based on the detailed temporal score shared by all performers, the 81 ninety-minute videos can be synchronised in post-production. These 81 synchronised videos will be used to generate two new projects: firstly, a large-scale video wall in which they unfold contemporaneously; and secondly, a video installation in which the 81 videos are mapped onto multiple surfaces and inter-spliced to explore their collective potential