Changes in optical characteristics induced by polymer blending in printed colloidal quantum dots microlasers

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• On-chip microlasers are crucial for diverse applications requiring precise control.
• Existing microlaser fabrication methods can be complex and costly.

Purpose of the Study:

• To develop a novel method for fabricating on-chip microlasers using printable colloidal quantum dots (CQDs).
• To investigate the effect of polymer blending on microlaser performance, including spectral purity and lasing characteristics.

Main Methods:

• Utilized pixelated printing of Cadmium Selenide/Zinc Sulfide (CdSe/ZnS) CQDs.
• Incorporated quantum dot self-assembly and an external cavity-free configuration.
• Modified the CQD matrix by blending varying concentrations of polystyrene (PS) polymer.

Main Results:

• Achieved on-chip microlasers with improved spectral purity through polymer blending.
• Observed a transition from quasitoroid to microdisk profiles with increasing PS concentration.
• Demonstrated a significant increase in lasing threshold and a 25 nm blue-shift in emission wavelength with low PS concentrations.

Conclusions:

• The developed printing technology and low-cost polymer blending method enable efficient fabrication of high-performance microlasers.
• These findings facilitate advancements in printable photonics and electronics for applications like microlaser displays and sensors.