Optically Induced Field-Emission Source Based on Aligned Vertical Carbon Nanotube Arrays

Area of Science:

• Materials Science
• Physics
• Nanotechnology

Background:

• Carbon nanotubes (CNTs) are utilized in optically induced field-emission due to their field enhancement and light absorption.
• Vertical carbon nanotube arrays (VCNTAs) offer potential as high-density electron sources.

Purpose of the Study:

• To investigate the performance of VCNTAs as high-density electron sources.
• To analyze the optically induced field emission mechanism in VCNTAs under varying conditions.

Main Methods:

• Fabrication of VCNTAs.
• Application of high electric fields and laser illumination.
• Modulation of electron emission using laser pulses.
• Analysis of emission sensitivity to laser intensity and polarization.

Main Results:

• VCNTAs function as high-density electron sources.
• Electron emission is modulated by laser pulses, sensitive to laser intensity via a power law.
• The emission mechanism is consistent with optically induced field emission followed by over-the-barrier emission.
• Observed polarization dependence follows a cosine behavior, supporting optically induced field emission.

Conclusions:

• VCNTAs are effective for optically induced field emission.
• The emission process is well-described by a combination of optically induced field emission and over-the-barrier emission.
• Laser polarization is a critical factor in VCNTAs' electron emission properties.