Deconvolution of the biexciton structure of monolayer MoSe₂ in spectroscopic ellipsometric data: a comparison of maximum-entropy methods

The detection of weak features in spectra remains a challenge. Differentiation remains a standard method, but maximum-entropy filters provide an alternative. Using dielectric-function data for MoSe₂ as a test case, we compare the capabilities of two maximum-entropy filters, the original Burg version and its corrected offshoot, to detect the biexciton and determine its energy. In contrast to differentiation, both approaches detect the biexciton. However, neither provides accurate values of the excitonic transition energies in this spectral range, although the Burg version is somewhat better.