Study of the interplay between pseudogap and antiferromagnetic correlations in electron-doped cuprates via TR-ARPES

In recent years, various angle-resolved photoemission spectroscopy (ARPES) studies focused on electron-doped cuprate superconductors to explore the similarities and differences between the two sides of the cuprates phase diagram. The pseudogap (PG) is a well-known phenomenon in the physics of high-temperature superconductors but despite numerous theoretical and experimental works, the origin of the PG in the cuprates is still under debate. Contrary to the hole-doped counterpart, antiferromagnetic (AF) correlations in the electron-doped side are stronger, offering the unique opportunity to explore the close interplay between AF, superconductivity, PG and other underlying phases. By exploiting time-resolved ARPES, we investigate the transient evolution of the low-energy density of state of the optimally doped Nd_2-xCe_xCuO₄ (NCCO, x=0.15). In particular, by studying the temperature-dependence of the PG spectral features, we demonstrate the direct relation between PG and spin correlation length and provide evidence for the primary role of AF correlations in determining the PG in electron-doped cuprates.