Electronic compressibility of layer polarized bilayer graphene

Understand

We report on a capacitance study of dual gated bilayer graphene.

• The measured capacitance allows us to probe the electronic compressibility as a function of carrier density, temperature, and applied perpendicular electrical displacement D.
• As a band gap is induced with increasing D, the compressibility minimum at charge neutrality becomes deeper but remains finite, suggesting the presence of localized states within the energy gap.
• Temperature dependent capacitance measurements show that compressibility is sensitive to the intrinsic band gap.