title: Illuminating the second conduction band and spin-orbit energy in single wurtzite InP nanowires.
abstract: We use polarized photoluminescence excitation spectroscopy to observe the energy and symmetry of the predicted second conduction band in 130 nm diameter wurtzite InP nanowires. We find direct spectroscopic signatures for optical transitions among the A, B, and C hole bands and both the first and the second conduction bands. We determine that the splitting between the first and second conduction bands is 228 ± 7 meV in excellent agreement with theory. From these energies we show that the spin-orbit energy changes substantially between zinc blende and wurtzite InP. We discuss the two quite different solutions within the quasi-cubic approximation and the implications for these measurements. Finally, the observation of well-defined optical transitions between the B- and C-hole bands and the second conduction band suggests that either the theoretical description of the second conduction band as possessing Γ8 symmetry is incomplete, or other interactions are enabling these forbidden transitions.
authors.affiliation: Department of Physics, University of Cincinnati , Cincinnati, Ohio 45221-0011, United States.
authors.forename: Saranga
authors.initials: S
authors.lastname: Perera
authors.forename: Teng
authors.initials: T
authors.lastname: Shi
authors.forename: Melodie A
authors.initials: MA
authors.lastname: Fickenscher
authors.forename: Howard E
authors.initials: HE
authors.lastname: Jackson
authors.forename: Leigh M
authors.initials: LM
authors.lastname: Smith
authors.forename: Jan M
authors.initials: JM
authors.lastname: Yarrison-Rice
authors.forename: Suriati
authors.initials: S
authors.lastname: Paiman
authors.forename: Qiang
authors.initials: Q
authors.lastname: Gao
authors.forename: Hark Hoe
authors.initials: HH
authors.lastname: Tan
authors.forename: Chennupati
authors.initials: C
authors.lastname: Jagadish
mesh_terms: D007204:Indium / Q000737:chemistry*; D008027:Light; D053770:Nanowires / Q000737:chemistry*; D009915:Orbit; D010316:Particle Size; D010720:Phosphines / Q000737:chemistry*; D013057:Spectrum Analysis; D013499:Surface Properties; D015032:Zinc / Q000737:chemistry*
chemical_list: D010720:Phosphines; D007204:Indium; D015032:Zinc; C090882:indium phosphide