Fig. 3: Experimental and theoretical RIXS spectra.

a The same RIXS spectrum as that in Fig. 1d while the elastic peak was subtracted from data, leaving only four Raman features. The colored solid lines are fitting results of each Raman feature. The gray solid line is the sum of the fitting results of the four Raman peaks. b RIXS spectra simulated by atomic multiplet theory. The broad peak at ~0.5 eV consists of 0.3 and 0.7 eV excitations, which are respectively d − d transitions among the e_g − e_g and e_g − t_2g orbitals. The broad 2.5 eV high-energy peak consists of multiple excited states of total spin quantum number S = 1. c Schematic cartoons illustrating the spin and orbital characters of the ground state and the low-energy excited states. d Dynamical spin structure factor S(q = 0, ω) and (non-spin-flip) orbital structure factor O(q = 0, ω) calculated using the multiplet model defined in the text.