Crossover between electromagnetically induced transparency and Autler–Townes splitting with dispersion

Based on Akaike's information criterion (AIC) for a coherently driven ensemble of cold rubidium atoms, we study the crossover between electromagnetically induced transparency (EIT) and Autler–Townes (AT) splitting from the dispersion as well as the absorption viewpoint. We find that the dispersion signal is more sensitive than the absorption signal, showing more pronounced features in the Akaike per-point weights spectrum, which provides a cleaner way of discerning EIT from AT splitting.