The Raman scattering with local optical excitation from the Majorana edge modes of Kitaev spin liquids and topological superconductors is studied theoretically. Although the effective one-dimensional model is common between these two cases, the coupling to the electromagnetic field is different. It is found that the Raman spectrum at low energy scales with ${\omega }^3$ in Kitaev spin liquids while it shows the gap in topological superconductors. This is in sharp contrast to the infrared absorption, where the spectrum shows the gap in Kitaev spin liquids, while it behaves as $\sim {\omega }^2$ in topological superconductors. This indicates that the electrodynamics of Majorana edge modes depends on their higher-dimensional origins. A realistic estimate of the Raman scattering intensity is given for $\alpha \text{−}{\mathrm{RuCl}}_3$ as a candidate for a Kitaev spin liquid.

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• Edge states
• Majorana fermions
• Quantum spin liquid
• Topological superconductors
• Kitaev model
• Raman spectroscopy