title: Polarized light absorption in wurtzite InP nanowire ensembles.
abstract: We investigate the absorption properties of ensembles of wurtzite (WZ) InP nanowires (NWs) by high-resolution polarization-resolved photoluminescence excitation (PLE) spectroscopy at T = 10 K. The degree of linear polarization of absorbed light, ρ(abs), resulting from the PLE spectra is governed by a competition between the dielectric mismatch effect and the WZ selection rules acting differently on different optical transitions. These two contributions are deconvoluted with the help of finite-difference time-domain simulations, thus providing information about the symmetry of the three highest valence bands (A, B, and C) of WZ InP and the extent of the spin-orbit interaction on these states. Moreover, ρ(abs) shows two characteristic dips corresponding to the two sharp A and B exciton resonances in the PLE spectra. A model developed for the dip in A provides the first experimental evidence of an enhancement in the dielectric mismatch effect originating from the Coulomb interaction between electron and hole.
authors.affiliation: Dipartimento di Fisica and CNISM, Sapienza Università di Roma , Piazzale A. Moro 2, 00185 Roma, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: De Luca
authors.forename: Attilio
authors.initials: A
authors.lastname: Zilli
authors.forename: H Aruni
authors.initials: HA
authors.lastname: Fonseka
authors.forename: Sudha
authors.initials: S
authors.lastname: Mokkapati
authors.forename: Antonio
authors.initials: A
authors.lastname: Miriametro
authors.forename: Hark Hoe
authors.initials: HH
authors.lastname: Tan
authors.forename: Leigh Morris
authors.initials: LM
authors.lastname: Smith
authors.forename: Chennupati
authors.initials: C
authors.lastname: Jagadish
authors.forename: Mario
authors.initials: M
authors.lastname: Capizzi
authors.forename: Antonio
authors.initials: A
authors.lastname: Polimeni
keywords: InP nanowires; dielectric mismatch; excitons; photoluminescence excitation; wurtzite band structure