The optical conductivity of high-temperature superconductors

Abstract

Abstract: This chapter discusses some of the current topics in the analysis of the optical conductivity of high-temperature cuprate superconductors. It presents a detailed description of the optical response in conducting media, stressing the points relative to strongly correlated systems. The pseudogap response in the normal state of hole-doped cuprates is extensively discussed in terms of spectral weight and the scattering rate. This chapter also discusses which changes the optical conductivity undergoes when moving, in the normal state, from the underdoped to the overdoped regime. A spectral weight analysis is utilized to understand the normal state gap in electron doped materials. The superconducting state is discussed in terms of the superconducting gap, kinetic energy changes in the transition and the analysis of the I 2 χ ( ω ) Eliashberg function characterizing the glue that keeps the pairs together. The chapter closes with a very brief overview of new systems such as MgB 2 and pnictide superconductors.