On the basis of the phenomenological Ginzburg-Landau model we calculate the critical current of the domain-wall superconducting channel formed in flux-coupled superconductor/ferromagnet (S/F) hybrids in the presence of the nonuniform magnetic field of the domain walls. It is shown that the current-carrying ability in such S/F systems in the domain-wall superconducting state differs for the positive and negative directions of the injected current with respect to the parity-breaking vector, which is proportional to V x M and thus determined by the local magnetization vector M(r) in the ferromagnetic substrate. We demonstrate that in such S/F systems the realization of the so-called diode effect is possible for both laterally infinite and mesoscopic structures.

Local electronic properties of quasi-two-dimensional Pb(111) islands with screw dislocations of different types on their surfaces were experimentally studied by means of lowtemperature scanning tunneling microscopy and spectroscopy in the regime of constant current. A comparison of the topography map, the maps of tunneling current variation, and the differential tunneling conductance acquired simultaneously allows one to visualize the hidden parts of the dislocation loops under the sample surface. We demonstrate that two closely positioned screw dislocations with the opposite Burgers vectors can either (i) connect to each other by the sub-surface dislocation loop or (ii) generate independent hidden edge dislocation lines, which run toward the perimeter of the Pb island. In addition, we found a screw dislocation, which does not produce outcoming sub-surface dislocation loops. Screw dislocations and the hidden dislocation lines are the source of the non-quantized variation of the local thickness of the Pb terraces, affecting the local electronic properties.

The dynamics of domain walls in optical bistable systems with pump and loss is considered. It is shown that an oscillating component of the pump affects the average drift velocity of the domain walls. The cases of harmonic and biharmonic pumps are considered. It is demonstrated that in the case of biharmonic pulse the velocity of the domain wall can be controlled by the mutual phase of the harmonics. The analogy between this phenomenon and the ratchet effect is drawn. Synchronization of the moving domain walls by the oscillating pump in discrete systems is studied and discussed.

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