Laterally emitted surface second harmonic generation in a single ZnTe nanowire

Area of Science:

• Nanophotonics and nonlinear optics.

Background:

• Second Harmonic Generation (SHG) is a key nonlinear optical process.
• Surface SHG in nanowires offers unique light manipulation possibilities.

Purpose of the Study:

• To directly observe and characterize laterally emitted surface SHG in a single Zinc Telluride (ZnTe) nanowire.
• To investigate the influence of laser polarization on surface SHG properties.

Main Methods:

• Direct optical observation of surface SHG emission from a ZnTe nanowire.
• Experimental control and analysis of pumping laser polarization.
• Numerical simulations to confirm experimental observations.

Main Results:

• Observed highly directional surface SHG radiating vertically to the nanowire axis.
• Achieved high conversion efficiency (5 × 10⁻⁶) and low divergence angle (4°).
• Demonstrated dependence of SHG polarization, intensity, and direction on laser polarization.

Conclusions:

• Lateral surface SHG in ZnTe nanowires is efficiently generated and highly directional.
• ZnTe nanowires are promising for developing novel photonic devices.
• Potential applications include short-wavelength nanolasers, nonlinear microscopic imaging, and integrated photonics.