Pattern induced phase transition of vortex motion in high-Tc films

Abstract

A micropattern induced transition in the mechanism of vortex motion and vortex mobility is demonstrated for high-Tc films. The competition between the anomalous Hall effect and the guidance of vortices by rows of microholes (antidots) leads to a sudden change in the direction of vortex motion that is accompanied by a change of the critical current density and microwave losses. The latter demonstrates the difference in vortex mobility in the different phases of vortex motion in between and within the rows of antidots.

Regimes of flux transport at microwave frequencies in nanostructured high-Tcfilms

“…From Hall measurements we know that this second minimum is caused by guided motion of flux, i.e., vortex or flux motion within the rows of antidots. 11,29 At lower temperatures the vortex-antidot interaction becomes larger. If the spacing between adjacent antidots is small enough, vortices will move from antidot to antidot even if the directing of motion is not identical to the direction of the driving Lorentz force.…”

Strong field-matching effects in superconducting YBa2Cu3O7−δSwiecicki1, Ulysse2, Wolf3 et al. 2012Phys. Rev. B545523View full textAdd to dashboardCite

“…That is about one order-of-magnitude better than achieved by physically patterning the superconductors via lithography and etching (e.g. introducing arrays of holes) 6,7,9,14,[18][19][20] , which dramatically increases -up to the kGauss range-the field range in which the artificial energy landscape is dominant. In addition, and crucially, the method developed here provides with the unique ability to adjust the depth of the landscape energy wells.…”

“…3 . We argue that this behaviour is connected to flux channelling across the energy landscape, 1,5-7 Besides directing vortex motion along preferred directions [5][6][7] (the energy landscape x and y axes), channelling enhances vortex mobility for fields in which the flux lattice does not match the pinning potential (i.e. for fields different from B=B 1, 2B 1 … etc) 1 .…”

Dual cut-off direct current-tunable microwave low-pass filter on superconducting Nb microstrips with asymmetric nanogrooves

“…The dynamics of Abrikosov vortices at mw frequencies has been extensively studied both theoretically [18][19][20][21][22][23] and experimentally 6,9,10,[14][15][16][17][18][24][25][26][27][28] . The central notion in the theoretical treatment of the ac-driven vortex dynamics is the depinning frequency 18,24 .…”

“…Superconducting circuit elements exploited in magnetic fields are known to suffer from losses due to motion of Abrikosov vortices 9,10 . Unless pinned, they increase noise and bit error rate in quantum interference devices (SQUIDs) 11 , raise unwanted vortex-assisted photon-count rates in detectors 12 , and reduce quality factors 5,6 and power handling capabilities 13 .…”