Spin fluctuations on the verge of Mott localization*

We investigate the effects of local, transverse spin fluctuations on transport and thermodynamic quantities in the proximity of a paramagnetic Mott transition. Low temperature Fermi liquid coherence is seen to cross over to universal power laws in resistivity, optical conductivity and specific heat at higher temperatures and frequencies. Striking agreement with the normal phase properties of LSCO and BSSCO series of high temperature superconductors (HTS) is found. We conclude that the anomalous properties of HTS above the superconducting dome originate from spin fluctuation scattering concomitant to Mott localization.