Two-Dimensional Bismuthene Showing Radiation-Tolerant Third-Order Optical Nonlinearities

Area of Science:

• Materials Science
• Optics
• Aerospace Engineering

Background:

• Space exploration demands radiation-resistant materials, especially for nonlinear optical devices.
• Two-dimensional (2D) materials show potential, but their radiation response is poorly understood.
• Previous work fabricated 2D bismuthene for laser mode-locking.

Purpose of the Study:

• Evaluate the space radiation adaptability of 2D bismuthene.
• Investigate radiation effects on nonlinear optical properties.
• Provide guidelines for optimizing 2D bismuthene for space applications.

Main Methods:

• Fabrication of 2D bismuthene using a bottom-up approach.
• Exposure to simulated space radiation (⁶⁰Co γ-rays and electron irradiation).
• Characterization of third-order nonlinear optical responses and saturable absorption.
• Ultrafast spectroscopy to analyze excited-state dynamics and damage mechanisms.

Main Results:

• As-synthesized 2D bismuthene demonstrated strong third-order nonlinear optical responses into the near-infrared.
• Bismuthene exhibited only slight degradation in saturable absorption after irradiation.
• Ultrafast spectroscopy revealed fundamental excited-state dynamics post-radiation.

Conclusions:

• 2D bismuthene is a promising radiation-resistant material for space-based nonlinear optical applications.
• The material's performance is largely maintained under simulated space radiation conditions.
• Understanding excited-state dynamics aids in optimizing bismuthene for future space missions.