Tuning Lasing Emission toward Long Wavelengths in GaAs-(In,Al)GaAs Core–Multishell Nanowires

Abstract

Semiconductor nanowire (NW) lasers are attractive as integrated on-chip coherent light sources with strong potential for applications in optical communication and sensing. Realizing lasers from individual bulk-type NWs with emission tunable from the near-infrared to the telecommunications spectral region is, however, challenging and requires low-dimensional active gain regions with an adjustable band gap and quantum confinement. Here, we demonstrate lasing from GaAs-(InGaAs/AlGaAs) core-shell NWs with multiple InGaAs quantum wells (QW) and lasing wavelengths tunable from ∼0.8 to ∼1.1 μm. Our investigation emphasizes particularly the critical interplay between QW design, growth kinetics, and the control of InGaAs composition in the active region needed for effective tuning of the lasing wavelength. A low shell growth temperature and GaAs interlayers at the QW/barrier interfaces enable In molar fractions up to ∼25% without plastic strain relaxation or alloy intermixing in the QWs. Correlated scanning transmission electron microscopy, atom probe tomography, and confocal PL spectroscopy analyses illustrate the high sensitivity of the optically pumped lasing characteristics on microscopic properties, providing useful guidelines for other III-V-based NW laser systems.

Correlated Nanoscale Analysis of the Emission from Wurtzite versus Zincblende (In,Ga)As/GaAs Nanowire Core–Shell Quantum Wells

“…Keywords nanowire, (In,Ga)As quantum well, polytype, cathodoluminescence, atom probe tomography, nano-focused x-ray diffraction This study investigates the influence of the crystal phase on the emission characteristics of (In,Ga)As quantum wells (QWs) on GaAs nanowires (NWs). Ternary group-IIIarsenide core-shell QWs have shown great promise in NW-based emitters/lasers [1][2][3][4] and detectors/solar cells. [5][6][7][8] Notably, (In,Ga)Asbased emitters have the potential to operate at the so-called telecommunication band; 9 such a combination of nanoscale emitters with Si waveguides promises to revolutionize the speed and energy efficiency of on-chip information transfer.…”

Optical Study of p-Doping in GaAs Nanowires for Low-Threshold and High-Yield Lasing

“…Common approaches to optimize the lasing threshold of a NWL include the introduction of single or multiple quantum wells, [22][23][24][25][26][27] quantum dots 28,29 or photonic crystals. 16,30 These methods rely on optimizing either the luminescence quantum efficiency QE = k r /(k r + k nr ) (where k r and k nr are the radiative and non-radiative rates, respectively 31 ) or the modegain spatial overlap.…”

Tailoring Spectral and Temporal Properties of Semiconductor Nanowire Lasers

“…Furthermore, core–shell structures were also used to tune lasing toward technically highly interesting regions, such as the telecom wavelength. In GaAs–(In,Al)GaAs core–multishell nanowires the emission was tuned by increasing the In content from ≈800 to ≈1100 nm at 10 K . Yet, still at room temperature a tunability from ≈885 to ≈932 nm was observed.…”