  Networks of graphene-based topological domain walls function as nano-scale
interferometers of zero-line modes, with magnetic field and(or) scalar
potential as the controlling parameters. In the absence of externally applied
magnetic or electrical field, strain induces pseudomagnetic field and scalar
potential in graphene, which could control the interferometers more
efficiently. Two types of strains are considered: (i) Horizontally bending the
graphene nanoribbon into circular arc induces nearly uniform pseudomagnetic
field; (ii) Helicoidal graphene nanoribbon exhibit nonuniform pseudomagnetic
field. Both types of strain induce small scalar potential due to dilatation.
The interferometers are studied by transport calculation of the tight binding
model. The transmission rates through the interferometer depend on the strain
parameters. An interferometer with three loops is designed, which could
completely switch the transmitting current from one export to the other.
