Introducing Artificial Pinning Centers Into YBCO Thin Films to Improve Surface Resistance in a DC Magnetic Field

Microwave Response of Nanostructured High-Tc Superconductor Thin Films

“…The results indicate that the implantation of nano-sized inclusions such as dielectric nanoparticles or radiation structural defects can decrease the microwave surface resistance in the Meissner state and can significantly improve the superconductor characteristics in the microwave frequency range. This effect was observed in some recent experimental works [9][10][11][12][13][14][15].…”

“…In addition, the dielectric nanoparticles (as well as point-like radiation defects) implanted in the matrix of a HTS film can significantly improve its characteristics at microwave frequencies. Namely, these implanted zero-dimensional nano-sized objects can decrease the surface resistance in the Meissner state [12,13] and eliminate the oscillations of Abrikosov vortices and related microwave energy losses, thus decreasing the contribution of Abrikosov vortices to the value in the mixed state of a type-II superconductor [14,15]. In the present work, we consider the effect of the addition of point-like defects on the microwave surface resistance value ( ) in the Meissner state of a superconductor and demonstrate how this treatment can significantly decrease ( ) value at least at low temperatures.…”

Improvement of microwave characteristics for high-T c superconductor (YBCO) films by ion irradiation treatment

“…about 10 11 cm −2 -similar to the S1 dose in the present work), mainly leads to the formation of additional point-like structural defects [5,6,24]. The latter manifests itself through enhanced vortex pinning and a related increase in the critical current density as well as a decrease in rf loss, caused by vortex oscillations in the applied rf field [14][15][16]. Another effect that arises due to the insertion of additional point-like structural defects concerns changes in the electron properties of moderately irradiated superconductors; namely, the enhancement of quasiparticle scattering by structural defects and a corresponding increase in the electron momentum relaxation rate.…”

“…On the other hand, as observed from a few experimental works, the incorporation of dielectric nanoparticles, as well as the formation of point-like irradiation defects in the matrix of HTS film, can significantly improve its microwave characteristics. For instance, the inserted dielectric nanoparticles and nanorods of different nature and content, as well as radiation nano-sized defects, can noticeably decrease the surface resistance in the Meissner state [12,13] and contribution to Abrikosov vortex oscillations and related microwave energy losses to the surface resistance value in the mixed state of a superconductor [14][15][16]. In addition, there are more sophisticated possibilities to use nanostructured superconducting materials in electronics [17,18].…”