title: Plasmons and screening in monolayer and multilayer black phosphorus.
abstract: Black phosphorus exhibits a high degree of band anisotropy. However, we find that its in-plane static screening remains relatively isotropic for momenta relevant to elastic long-range scattering processes. On the other hand, the collective electronic excitations in the system exhibit a strong anisotropy. Band nonparabolicity, due to interband couplings, leads to a plasmon frequency which scales as nβ, where n is the carrier concentration, and β<1/2. Screening and charge distribution in the out-of-plane direction are also studied using a nonlinear Thomas-Fermi model.
authors.affiliation: IBM T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, USA and Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA and Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Tony
authors.initials: T
authors.lastname: Low
authors.affiliation: Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Roldán
authors.affiliation: Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089, USA.
authors.forename: Han
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA.
authors.forename: Fengnian
authors.initials: F
authors.lastname: Xia
authors.affiliation: IBM T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, USA.
authors.forename: Phaedon
authors.initials: P
authors.lastname: Avouris
authors.affiliation: Instituto de Ciencia de Materiales de Aragón and Departamento de Física de la Materia Condensada, CSIC-Universidad de Zaragoza, E-50009 Zaragoza, Spain.
authors.forename: Luis Martín
authors.initials: LM
authors.lastname: Moreno
authors.affiliation: Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Guinea