Fig. 4: Robust hysteresis and ferroelectric switching in multilayer OSH devices with Bernal bilayer and trilayer graphene.
From: Room temperature ferroelectricity in monolayer graphene sandwiched between hexagonal boron nitride
a nHall as a function of Vb/db during forward (blue) and backward (red) sweeps in OSH device 5. b The extracted polarization hysteresis loop of OSH device 5. c Atomic illustration of OSH device 5 showing the parallel-orientation of bilayer graphene and top/bottom hBN layers. The local registry with vertical B-C-C-h alignment possesses a negative polarization. d The nHall vs Vb/db loop of OSH device 6 with trilayer graphene. e The polarization hysteresis loop of device 6. f The atomic arrangement of the OSHs based on trilayer graphene with vertical B-C-C-C-h alignment. g Structural evolution of the OSHs under co-sliding motions of Bernal stacked multilayer graphene and hBN. Pink background marks the stationary bottom hBN layer. Brown and green arrows mark the sliding direction of graphene and hBN, respectively. h nHall hysteresis loops of OSH device 6 under different Vbini at T = 300 K. i The Rxy response of OSH device 6 under 50,000 electric pulses (Vb = +20/−20 V) at T = 300 K & B = 1 T. Inset is the close-view of 87 switches within 500 s.
