Cavity-Mediated Radiative Energy Transfer Enables Stable, Low-Threshold Lasing in Hybrid Quantum Dot-Nanoplatelet...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Colloidal semiconductor nanocrystals offer solution processability and tunable spectra for optoelectronics.
• Limitations in lasing applications include high thresholds, Auger recombination losses, and environmental sensitivity.
• Quantum dots (QDs) and nanoplatelets (NPLs) are key nanomaterials in this field.

Purpose of the Study:

• To overcome limitations in colloidal nanocrystal-based lasing.
• To develop hybrid microscale supraparticles for efficient optical amplification.
• To create a stable and tunable platform for optoelectronic devices and pigment technologies.

Main Methods:

• Fabrication of hybrid microscale supraparticles using core/shell CdSe/ZnS QDs and CdSe/Cd_xZn_1-xS NPLs.
• Utilizing cavity-mediated energy funneling and coupling for excitation transfer.
• Characterization of lasing performance, including threshold and stability under various conditions.

Main Results:

• Achieved stable whispering gallery mode lasing with a low threshold of 0.35 mJ/cm².
• Demonstrated efficient energy transfer from broadband absorbing QDs to narrow emitting NPLs.
• Supraparticles maintained optical performance after prolonged exposure to air, water, and continuous irradiation.

Conclusions:

• Hybrid supraparticles composed of QDs and NPLs effectively overcome limitations in nanocrystal lasing.
• The developed platform offers a versatile and programmable approach for optical amplification and tunable emission.
• The findings present practical advantages for optoelectronic devices and advanced pigment applications.