Topological solitons in a vacuumless system

We investigate a model for a real scalar field in bidimensional space-time, described in terms of a positive semi-definite potential that presents no vacuum state. The system presents topological solutions of the BPS type, with energy density that follows a Lorentzian law. These BPS solutions differ from the standard $\tanh$-type kink, but they also support bosonic and fermionic zero modes.