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DOE OSTI · 1822807

Prospects and challenges of colloidal quantum dot laser diodes

Jung, Heeyoung·Ahn, Namyoung·Klimov, Victor Ivanovich
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Abstract

Colloidal quantum dots (QDs) combine the superior light-emission characteristics of quantum-confined semiconductors with the chemical flexibility of molecular systems. We find that these properties could, in principle, enable solution-processable laser diodes with an ultrawide range of accessible colours. However, the realization of such devices has been hampered by fast optical gain decay due to non-radiative Auger recombination and poor stability of QD solids at the high current densities required for the lasing regime. Recently, these problems have been resolved, which resulted in the development of electrically pumped optical gain devices operating at ultrahigh current densities of around 1,000 A cm -2 . The next step is the realization of a QD laser diode (QLD). Here we assess the status of the QD lasing field, examine the remaining challenges on the path to a QLD and discuss practical strategies for attaining electrically pumped QD lasing.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYdiode lasersnanophotonics and plasmonics

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Jung, Heeyoung, Ahn, Namyoung, Klimov, Victor Ivanovich. 2021-08-27. Prospects and challenges of colloidal quantum dot laser diodes. https://doi.org/10.1038/s41566-021-00827-6

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