Anomalous conductance fluctuations in bilayer graphene in h-BN layers

In recent experiments, we have succeeded to fabricate a h-BN/graphene/h-BN heterostructure showing a good mobility reaching to 8 × 10
⁴
cm
²
/Vs. And then, we observed a transition between conductance fluctuations at low magnetic field less than 0.5 T and regular Shubnikov-de Haas oscillation at higher than the magnetic field. We analyzed the fluctuations compared to that of former graphene samples on SiO
₂
layer, especially focused on the amplitude and the carrier density dependence. We will discuss the anomalous behavior breaking the universality in the conductance fluctuations of the bilayer graphene in a quasi-ballistic transport regime.