Highly linear polarized emission at telecom bands in InAs/InP quantum dot-nanowires by geometry tailoring

Area of Science:

• Optoelectronics
• Nanotechnology
• Materials Science

Background:

• Optoelectronic devices based on nanowires (NWs) require precise geometric engineering for polarized light applications.
• Achieving controlled polarization in light sources and photodetectors is crucial for advanced optical technologies.

Purpose of the Study:

• To develop a growth procedure for producing InAs/InP quantum dot-nanowires (QD-NWs) with an elongated, asymmetric cross-section.
• To investigate the impact of this asymmetric geometry on the polarization properties of emitted light.

Main Methods:

• Utilized the vapor-liquid-solid (VLS) method with molecular beam epitaxy (MBE).
• Interrupted sample rotation during InP shell growth to create hexagonal asymmetric (HA) NWs.
• Performed polarization-resolved photoluminescence (PL) measurements.

Main Results:

• Successfully fabricated HA InAs/InP QD-NWs with distinct long and short cross-section axes.
• Demonstrated that NW asymmetry significantly influences light polarization, with photons predominantly polarized parallel to the long axis.
• Achieved a high degree of linear polarization (DLP) up to 91%, a state-of-the-art value for QD-NWs.

Conclusions:

• The developed growth protocol enables the creation of asymmetric QD-NWs with highly polarized light emission.
• This method is compatible with existing applications, paving the way for advanced polarized light-emitting diodes and photodetectors.
• The engineered HA NWs offer a promising platform for next-generation polarization-sensitive optoelectronic devices.