Toward Chiral Lasing from All-Solution-Processed Flexible Perovskite-Nanocrystal-Liquid-Crystal Membranes

Area of Science:

• Optoelectronics
• Materials Science
• Nanotechnology

Background:

• Circularly polarized (CP) light is crucial for advanced optical applications like displays, imaging, data processing, and quantum communication.
• Existing CP light sources often lack flexibility, stability, or efficient fabrication methods.

Purpose of the Study:

• To demonstrate the first free-standing, flexible membrane device capable of generating CP amplified spontaneous emission (ASE) and lasing.
• To achieve high performance in terms of luminescence dissymmetry and operational stability in a solution-processable device.

Main Methods:

• Fabrication of a flexible membrane device using perovskite nanocrystals (PNCs) and cholesteric liquid crystals (CLCs) within a Fabry-Pérot cavity.
• Characterization of the device's CP ASE properties, including the dissymmetry factor (g_lum).
• Evaluation of the device's mechanical flexibility and long-term stability.

Main Results:

• The device successfully generated CP ASE with a record dissymmetry factor (g_lum) as high as 1.4, significantly outperforming previous CP luminescence from PNCs.
• Demonstrated exceptional ultraflexibility, maintaining ASE intensity after 100 bending cycles.
• Exhibited excellent stability, retaining 80% of its original intensity after 3 months.

Conclusions:

• This work presents the first CP ASE from a perovskite nanocrystal membrane with remarkably high g_lum.
• The developed device is ultraflexible, highly stable, and entirely solution-processable.
• Opens avenues for fabricating advanced, adaptable perovskite chiral laser devices for diverse applications.