Figure 3: Measured and calculated two-magnon Raman spectra.
From: Interplay of Dirac electrons and magnetism in CaMnBi2 and SrMnBi2
The low-temperature (10 K) two-magnon Raman spectra in the A1g (a–c) and B1g (d–f) channels (circles) compared with the calculated results based on the linear spin–wave theory without considering the magnon–magnon interactions (magenta lines) and the results taking into account the magnon–magnon interactions (black lines). The vertical dashed lines mark the characteristic frequencies that are independent of the symmetries and the magnon–magnon interactions. These two characteristic frequencies, in combination with the cutoff frequencies, determine the exchange energies J1, J2 and Jc (see Supplementary Note 2 and Supplementary Fig. 1 for details).
