Exciton Mott transition revisited

The dissociation of excitons into holes and electrons in photoexcited semiconductors, despite being one of the first recognized examples of a Mott transition, still defies a complete understanding, especially regarding the character of the transition, which is first order in some cases and second order in others. We tackle this issue by a recently proposed and very powerful variational technique, which extends the conventional Gutzwiller variational wavefunction and has been named ghost Gutzwiller wavefunction (g-GA). The results that we present [1] are in accordance with experiments and allow identifying the key parameter that controls the nature of the transition: the magnitude of the exciton binding energy.
[1] D. Guerci, M. Capone, M. Fabrizio (2018,arXiv:1810.01843).