Evolution of spin and lattice dynamics in a photodoped cuprate Mott antiferromagnet

Hole- and electron-doped cuprate Mott antiferromagnets host a rich variety of exotic quantum phenomena, most notably high-temperature superconductivity. Photodoping provides a distinct non-equilibrium pathway to introduce both electrons and holes simultaneously, enabling a dynamic interplay among charge, spin, and lattice degrees of freedom with no direct analog in thermal equilibrium. In this work, we excite the prototypical parent cuprate La₂CuO₄ with above-gap femtosecond pluses and probe its transient response via ultrafast time-resolved Raman spectroscopy. The measurements reveal pronounced time-dependent spectral modifications in both magnetic and lattice excitations, indicating the formation of a non-equilibrium electronic state whose behavior contrasts with that of the chemically doped counterparts.