Fig. 3: Universal behavior.
From: Asymmetric Rydberg blockade of giant excitons in Cuprous Oxide
The scaled difference \({{\Delta }}E/\hslash \gamma =({{{\Delta }}}_{0}-{{{\Delta }}}_{\max })/\gamma \) between the maxima and isosbestic points of the transmission signal does not depend on the pump intensity (see Fig. 1f, g) and is shown here as a function of the principal quantum number n of the probe excitons. For homogeneously broadened laser excitation, it becomes a universal quantity that only depends on the type of the interaction and is given by ΔE/ℏγ = 0.45 for van der Waals interactions, V(r) = C6/r6, as indicated by the dashed red line. Phonon coupling leads to asymmetric line broadening and causes slight deviations from this behavior (red solid line) in excellent agreement with the measurements shown by the black dots. Other potentials, such as direct dipole-dipole interactions, V(r) = C3/r3, do not match the observations (gray line). The error bars denote the standard deviation.
