  We report, based on its variation in electronic transport to coupled tension
and shear deformation, a highly sensitive graphene-based strain sensor
consisting of an armchair graphene nanoribbon (AGNR) between metallic contacts.
As the nominal strain at any direction increases from 2.5 to 10%, the
conductance decreases, particularly when the system changes from the
electrically neutral region. At finite bias voltage, both the raw conductance
and the relative proportion of the conductance depends smoothly on the gate
voltage with negligible fluctuations, which is in contrast to that of pristine
graphene. Specifically, when the nominal strain is 10% and the angle varies
from 0 degree to 90 degree, the relative proportion of the conductance changes
from 60 to 90%.
