Our more recent work on probing the topological states of PbSnSe in a superlattice structure has been published in Physics Review B. It is a milestone demonstrating a full spectroscopic study of the Dirac states of a topological material in a heterostructure using a non-surface sensitive probe. Our study also shows how the versatility of the PbSnSe system allows us to tune the Dirac mass and penetration depth of the topological states by simply changing the temperature. This is of important fundamental relevance to engineer Dirac fermions with a variable mass using an external continuous knob, without having to alter the sample characteristics.