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Highlyefficient solid-state light-emitting devices require semiconductorarchitectures equipped with high quantum efficiency and integratabilityon conductive substrates. Surface plasmon (SP)-mediated luminescenceenhancement has been considered as one of the most promising solutions,because SP resonance can greatly improve the radiative recombinationrate and be achieved using metal entities compatible with the electrodefabrication process. Nevertheless, metal/semiconductor heterostructureshave had several fabrication-compatible issues due to metal as a potentialcontaminant of the semiconductor. We present here a simple fabricationscheme for a metal-lined semiconductor nanotube heterostructure, inwhich a metal layer is selectively formed on the inner wall of thesemiconductor nanotube. The Ag-lining process in a ZnO nanotube resultedin 7.5-fold enhancement of the photoluminescence intensity at 11 K.This SP fabrication technique looks promising for highly efficientsolid-state lighting based on semiconductor nanostructures withoutdetrimental effects. [ABSTRACT FROM AUTHOR]

We present a first-principles many-body perturbation theory study of nitrophenyl-doped (6,5) single-walled nanotubes (SWCNTs) to understand how sp 3 doping impacts the excitonic properties. sp 3 -doped SWCNTs are promising as a class of optoelectronic materials with bright tunable photoluminescence, long spin coherence, and single-photon emission (SPE), motivating the study of spin excitations. We predict that the dopant results in a single unpaired spin localized around the defect site, which induces multiple low-energy excitonic peaks. By comparing optical absorption and photoluminescence from experiment and theory, we identify the transitions responsible for the red-shifted, defect-induced E 11 * peak, which has demonstrated SPE for some dopants; the presence of this state is due to both the symmetry-breaking associated with the defect and the presence of the defect-induced in-gap state. Furthermore, we find an asymmetry between the contribution of the two spin channels, suggesting that this system has potential for spin-selective optical transitions.

Due to their tunable bandgaps and strong spin-valley locking, transition metal dichalcogenides constitute a unique platform for hosting single-photon emitters. Here, we present a versatile approach for creating bright single-photon emitters in WSe 2 monolayers by the deposition of gold nanostars. Our molecular dynamics simulations reveal that the formation of the quantum emitters is likely caused by the highly localized strain fields created by the sharp tips of the gold nanostars. The surface plasmon modes supported by the gold nanostars can change the local electromagnetic fields in the vicinity of the quantum emitters, leading to their enhanced emission intensities. Moreover, by correlating the emission energies and intensities of the quantum emitters, we are able to associate them with two types of strain fields and derive the existence of a low-lying dark state in their electronic structures. Our findings are highly relevant for the development and understanding of single-photon emitters in transition metal dichalcogenide materials.