GUIDANCE OF VORTICES IN HIGH-T_C SUPERCONDUCTING THIN FILMS WITH SPECIAL ARRANGEMENT OF ANTIDOTS

Imaging and controlling vortex dynamics in mesoscopic superconductor–normal-metal–superconductor arrays

“…Beyond enhancing superconductivity, it is desirable to control vortex positions to predict vortex paths, as well as the fields surrounding the superconductor. The demonstration of locally probed and manipulated vortices [1][2][3][4][5][6][7][8][9][10][11][12][13][14] is relevant to a variety of technological applications, including quantum computation [15,16].…”

Guided Vortex Motion Control in Superconducting Thin Films by Sawtooth Ion Surface Modification

“…A continual struggle in the production of superconducting devices is the electrical noise induced from the movement of trapped magnetic flux . Methods of reducing the flux noise include pinning enhancement, − artificial defect pattern, − flux dams, or magnetic shielding . The most optimal strategy for the reduction of noise would be to remove the flux entirely, which may be achieved through the rectification of current (ratchet effect).…”

“…The ratchet effect can be simply produced by asymmetrical defects, for example, triangles and antidots. ,,− However, the maximum effect in these cases is limited by the artificial defect density and dimensions. These in itself are limited by the damage introduced into the superconductor as well as the technology used. , …”

Magnetization Ratchet in Cylindrical Nanowires

“…Magnetic quantum ratchets have been recently reported in artificially asymmetric graphene 1−3 or in superconducting systems where vortices are pinned at asymmetric substrates or by designed antidot arrays. 4,5 Nanopatterned magnetic films with asymmetrical holes or dots can also show a ratchet effect. 6,7 Skyrmion ratchets represent an ac current-based method for controlling the skyrmion position and motion for spintronic applications.…”

“…Many fascinating prototypes for magnetic ratchet effects are attracting attention, from fundamental to engineering functionality points of view. Magnetic quantum ratchets have been recently reported in artificially asymmetric graphene − or in superconducting systems where vortices are pinned at asymmetric substrates or by designed antidot arrays. , Nanopatterned magnetic films with asymmetrical holes or dots can also show a ratchet effect. , Skyrmion ratchets represent an ac current-based method for controlling the skyrmion position and motion for spintronic applications . Shift registers based on DW ratchets have been proposed in planar nanostrips where DWs experience an energy landscape engineered to favor unidirectional ratchetlike propagation. , The unidirectional motion of DWs has been proposed in memory devices based on in-plane field-controlled DW pinning and in chiral DWs exhibiting asymmetry in their speed with respect to magnetic fields for 2D data storage systems. , Different alternatives for the pinning/depinning of a DW in nanostrips have been attempted recently by various techniques, among others by geometrical notches and corners or under the action of local stray fields generated by neighboring tips or wires. , The DW ratchet effect was suggested for the DW motion in nanostrips with asymmetric notches, resulting in an asymmetric pinning depending on the DW motion direction …”