2D BP/InSe Heterostructures as a Nonlinear Optical Material for Ultrafast Photonics

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Black phosphorus (BP) and indium selenide (InSe) offer high charge carrier mobility.
• BP/InSe heterostructures combine these properties, enhancing BP's stability.
• Photonics applications of BP/InSe heterostructures remain underexplored.

Purpose of the Study:

• Fabricate a 2D BP/InSe heterostructure.
• Investigate its linear and nonlinear optical (NLO) absorption properties.
• Demonstrate its potential in photonics devices.

Main Methods:

• Liquid-phase exfoliation for 2D BP/InSe fabrication.
• UV-Vis-IR spectroscopy for linear absorption.
• Open-aperture Z-scan for NLO absorption.
• Integration into an erbium-doped fiber laser.

Main Results:

• Superior NLO properties of 2D BP/InSe confirmed.
• Stable 881 fs soliton pulses generated at 1.5 μm.
• Harmonic mode-locking of bound solitons and dark-bright soliton pairs achieved.
• Stable mode-locking maintained for days, overcoming BP instability.

Conclusions:

• The 2D BP/InSe heterostructure possesses excellent optical properties.
• It demonstrates significant potential for nano-photonics devices.
• Applications include double pulse laser sources and long-distance information transmission.