Fluctuations of Various Order Parameters in Cuprate and Fe-based Superconductors As Revealed by Microwave Absorption Measurements

Fluctuations of various order parameters are considered as the significant components of understanding the mechanism of high-T-c superconductivity. To study these fluctuations in the cuprate and Fe-based superconductors we use the joint measurements of direct current resistivity and non-resonant microwave absorption. Comparing data obtained with both methods allowed us to extract the contribution of dynamic charge density waves in La2-xSrxCuO4, superconducting fluctuations in Bi2Sr2Ca1-xYxCu2O8 and nematic fluctuations in FeTe1-xSex.