(Invited) Novel Luminescent Materials Based on Semiconductor Nanowires

Abstract

Recent work on the photoluminescence (PL) properties of InAsP/InP nanowires are reported. InP nanowires were grown on <111> Si substrates by the Au-assisted vapor-liquid-solid process in a gas source molecular beam epitaxy system. InAs y P 1-y segments were grown within the InP nanowires, creating single or multiple quantum dots structures. The quantum dot dimensions and composition were determined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive x-ray spectroscopy (EDX). PL from the quantum dot structures could be tuned by the InAs y P 1-y composition (y), or by the size of the quantum dot via the quantum confinement effect. Cathodoluminescence (CL) measurements confirmed localized emission from the quantum dots. To reduce detrimental surface states, the nanowires were passivated with an AlInP shell, which resulted in strong PL emission.

Photoluminescence and photocurrent from InP nanowires with InAsP quantum dots grown on Si by molecular beam epitaxy

“…The calculated interband emission wavelengths for the InAs 0.25 P 0.75 , InAs 0.50 P 0.50 , InAs 0.75 P 0.25 and InAs samples were 880-950 nm, 950-1150 nm, 1000-1400 nm, and 1000-1700 nm, respectively, in reasonable agreement with the observed PL emission. Cathodoluminescence measurements, reported elsewhere [30], indicated localized emission due to the QDs.…”