Infrared Spectroscopy of Dual-Gated Bilayer Graphene

We have performed infrared transmission spectroscopy measurements on dual-gated encapsulated bilayer graphene. In these measurements, we have observed intra- and inter-band resonances of bilayer graphene which we study as a function of magnetic field, filling factor, and displacement field. We will share comparisons between measurements of devices with metal and graphite gates. Methods of distinguishing sample resonances from resonances observed in the silicon and graphite gates will also be discussed.