Laser diodes based on solution‐processable materials can benefit numerous technologies
including integrated electronics and photonics, telecommunications, and medical
diagnostics. An attractive system for implementing these devices is colloidal semiconductor
quantum dots (QDs). The progress towards a QD laser diode has been hampered by rapid
nonradiative Auger decay of optical‐gain‐active multicarrier states, fast device degradation
at high current densities required for laser action, and unfavorable competition between …

In article number 2206613, Namyoung Ahn, Victor I. Klimov, and co-workers demonstrate
optically excited lasing in a fully functional colloidal quantum dot electroluminescent device
with an integrated optical resonator prepared as a distributed feedback grating, representing
an important milestone toward solution-processable laser diodes. The colloidal quantum
dots are cast from solution onto a grating and excited either electrically or optically to
produce multicolor output. Image credit: Albin Guyot.