0_9484 Vortices in high-T_c superconductors (HTSC) exhibit a very rich dynamics determined both by the materials intrinsic properties and by the material defects acting as pins. On one side, understanding pinning and controlling it through engineered defects is a pivotal topic in the pursuit of materials capable of withstanding high currents. On the other side, the quasiparticles relaxation processes responsible for the energy dissipation by vortex motion are deeply rooted in the complexity of these materials. Indeed, cuprate and iron-based SC present many complex features, from the common traits, such as the quasi-2D structure and an unconventional pairing mechanism, to the distinct ones, such as d-wave single gap vs multigap superconductivity. All these  features concur in shaping vortex dynamics in regimes ranging from dc, relevant for high field magnets, to high frequency, of interest in fundamental physics experiments applications [1], to non-equilibrium regimes attained at high vortex velocities, dictating the operating ranges of novel fluxonic devices. The experimental study of high frequency vortex dynamics with multi-frequency techniques [2] allows unravelling and disentangling several physical mechanisms [3]. The extraction of vortex parameters such as the flux-flow resistivity ρ_ff and the intrinsic (mass) anisotropy allows accessing material properties separately from extrinsic, pinning-dependent quantities, such as the pinning constant k_p and the thermal creep factor χ. On Fe-based SC we show how the field and angular dependence of ρ_ff in [4] is found to closely follow the single-band BGL scaling theory [5], with intrinsic (mass) anisotropy values ~2 irrespective of the temperature. In these materials we also study the effect of heavy ion irradiation, showing how the correlated pinning and the material anisotropy are affected. In Y-based SC studied in pristine conditions and with second-phase additions [1], we observe how the added disorder impacts differently the quasi-particles relaxation time (essentially unaffected) and the pinning strength k_p (increased). Finally, the vortex parameters analysis, also in comparison with recent results [6] on low T_c SC reconsidered for high frequency applications, sheds light on possible perspectives for large physics experiments.   
 Acknowledgements
Work partially supported by MIUR-PRIN Project “HIBiSCUS” - Grant 201785KWLE and by INFN CSN5 “SAMARA”. We acknowledge collaborations and fruitful discussions with V. Braccini, G. Celentano, G. Ghigo, G. Grimaldi, C. Pira, M. Putti, T. Puig.   
 Ref.s
 1    A. Alimenti et al, IEEE Instrum. Meas. Mag. 24, 12 (2021)
2    N. Pompeo et al, Measurement 184, 109937 (2021)
3    N. Pompeo et al, Low Temp. Phys. 46, 343–347 (2020)
4    N. Pompeo et al, Supercond. Sci. Technol. 33, 114006 (2020)
5    G. Blatter et al, Phys. Rev. Lett. 68, 875 (1992)
6    A. Alimenti et al, Supercond. Sci. Technol. 34, 014003 (2021)