Jun Zhu

Bernal bilayer graphene (BLG) offers a tunable platform to explore a rich variety of mesoscopic phenomena and their potential applications. In this talk, I will highlight a few advanced device structures we developed to study the quantum valley effect, gapless spin waves of a quantum Hall magnet and a Fabry-Perot interferometer. Using multi-layer graphite gating and precisely aligned split gates, we demonstrate precise resistance quantization of the quantum valley Hall kink states at zero magnetic field and an electric field operated topological switch. The resistance quantization remains very robust against temperature, only changing 3% at ~ 50 K. I will then describe an experiment probing the momentum dispersion of gapless spin wave excitations of a quantum Hall easy-plane canted-antiferrormagnet occurring at filling factor $\nu$=0 of BLG due to e-e interaction. Finally I will describe the fabrication and operation of a Fabry-Perot interferometer and Aharonov-Bohm oscillations at integer quantum Hall states. High sample quality, an electric-field-induced band gap, and advanced lithographic techniques together give BLG immense potential in probe many-body physics and realizing sophisticated quantum information devices.