Figure 2
From: Probing dynamics and pinning of single vortices in superconductors at nanometer scales
Vortex response and the structure of potential well 2 and comparison to simulations.
(a–d), Calculated vortex response to Fac = 8.89 fN in a potential well U(r) = −U0/(1 + (r/ξ)2) due to a single defect with U0 = 4 eV: (a), vortex ac displacement xac and yac; (b), vortex trajectory; (c), restoring force; and (d), the potential shifted to zero value at its minimum. The data points end where the activation barrier ΔU = 34kBT (see S9). (e–h), Measured vortex response in well 2: (e), displacements xac and yac in response to Fac = 8.89 fN, displaying a large softening peak in the middle of the well; (f), vortex trajectory with an ‘S’ shape; (g), restoring force showing a pronounced inflection point; and (h), the potential well with its minimum set to zero. The data points end where the vortex hopped into a different well. (i–l), Calculated vortex response in a potential well due to a cluster of four defects (see Figure 5a for locations of defects): (i), ac vortex displacement; (j), vortex trajectory; (k), restoring force; and (l), the potential with its minimum set to zero. The data points end where ΔU = 34kBT.
