Microwave response of Abrikosov vortices in superconductors with a different defect structure

Measurements of the microwave surface impedance Zs(T,H,/spl omega/) in the mixed state of high-temperature superconductors (HTS) provide valuable information on pinning and ac-dynamics of Abrikosov vortices in these highly anisotropic materials. Meanwhile, till now there is no full understanding of the numerous experimental results in this field and moreover, some of these experiments seem to be controversial and contradicting to existing theories of ac vortex dynamics in superconductors. In the present work the phenomenological theory of linear vortex response in the mixed state of superconductors at microwave frequencies is suggested with account for different possible types of lattice defects, which govern vortex pinning and dynamic properties. This model can be regarded as an extension of the well-known Coffey-Clem and Brandt theory which additionally accounts for specific peculiarities of vortex pinning and dynamics in superconductors with a different type of crystalline lattice disorder.