  We study how double-stranded DNA translocates through graphene nanogaps.
Nanogaps are fabricated with a novel capillary-force induced graphene nanogap
formation technique. DNA translocation signatures for nanogaps are
qualitatively different from those obtained with circular nanopores, owing to
the distinct shape of the gaps discussed here. Translocation time and
conductance values vary by $\sim 100$%, which we suggest are caused by local
gap width variations. We also observe exponentially relaxing current traces. We
suggest that slow relaxation of the graphene membrane following DNA
translocation may be responsible. We conclude that DNA-graphene interactions
are important, and need to be considered for graphene-nanogap based devices.
This work further opens up new avenues for direct read of single molecule
activitities, and possibly sequencing.
