  The multi-component nature of bilayer graphene (BLG), together with the
ability to controllably tune between the various ground state orders, makes it
a rich system in which to explore interaction driven phenomena. In the
fractional quantum Hall effect (FQHE) regime, the unique Landau level spectrum
of BLG is anticipated to support a non-Abelian even-denominator state that is
tunable by both electric and magnetic fields. However, observation of this
state, which is anticipated to be stronger than in conventional systems, has
been conspicuously difficult. Here we report transport measurements of a robust
even denominator FQHE in high-mobility, dual gated BLG devices. We confirm that
the stability of the energy gap can be sensitively tuned and map the phase
diagram. Our results establish BLG as a dynamic new platform to study
topological ground states with possible non-Abelian excitations.
