title: Two-dimensional exciton properties in monolayer semiconducting phosphorus allotropes.
abstract: Excitons play a key role in technological applications since they have a strong influence on determining the efficiency of photovoltaic devices. Recently, it has been shown that the allotropes of phosphorus possess an optical band gap that can be tuned over a wide range of values including the near-infrared and visible spectra, which would make them promising candidates for optoelectronic applications. In this work we carry out ab initio many-body perturbation theory calculations to study the excitonic effects on the optical properties of two-dimensional phosphorus allotropes: the case of blue and black monolayers. We elucidate the most relevant optical transitions, exciton binding energy spectrum as well as real-space exciton distribution, particularly focusing on the absorption spectrum dependence on the incident light polarization. In addition, based on our results, we use a set of effective hydrogenic models, in which the electron-hole Coulomb interaction is included to estimate exciton binding energies and radii. Our results show an excellent agreement between the many-body methodology and the effective models.
authors.affiliation: Istituto di Struttura della Materia of the National Research Council, Via Salaria Km 29.3, I-00016 Monterotondo Stazione, Italy and Instituto de Física Teórica, Universidade Estadual Paulista (UNESP), Rua Dr. Bento T. Ferraz, 271, São Paulo, SP 01140-070, Brazil. villegas@ift.unesp.br.
authors.forename: Cesar E P
authors.initials: CE
authors.lastname: Villegas
authors.affiliation: Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore.
authors.forename: A S
authors.initials: AS
authors.lastname: Rodin
authors.affiliation: Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore 117546, Singapore.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Carvalho
authors.affiliation: Instituto de Física Teórica, Universidade Estadual Paulista (UNESP), Rua Dr. Bento T. Ferraz, 271, São Paulo, SP 01140-070, Brazil. villegas@ift.unesp.br.
authors.forename: A R
authors.initials: AR
authors.lastname: Rocha