  Memory cells are an important building block of digital electronics. We
combine here the unique electronic properties of semiconducting monolayer MoS2
with the high conductivity of graphene to build a 2D heterostructure capable of
information storage. MoS2 acts as a channel in an intimate contact with
graphene electrodes in a field-effect transistor geometry. Our prototypical
all-2D transistor is further integrated with a multilayer graphene charge
trapping layer into a device that can be operated as a nonvolatile memory cell.
Because of its band gap and 2D nature, monolayer MoS2 is highly sensitive to
the presence of charges in the charge trapping layer, resulting in a factor of
10000 difference between memory program and erase states. The two-dimensional
nature of both the contact and the channel can be harnessed for the fabrication
of flexible nanoelectronic devices with large-scale integration.
