Electric field-induced Charging Could Improve Colloidal Quantum Dot Lasing

Researchers at Nanyang Technological University (NTU Singapore) have demonstrated tunable, controllable amplified spontaneous emission (ASE) in a colloidal semiconductor device via electric field-induced charging. Their work could open new avenues for achieving electrically pumped colloidal quantum dot (CQD) lasers. In experiments, the NTU scientists embedded CQDs between two electrodes to create an electric field to control and change the properties inside the CQDs. The researchers quantitatively determined the contribution of neutral, singly-, and doubly-charged CQDs to the ASE and demonstrated the dominant role of singly-charged CQDs in achieving a low ASE threshold. Specifically, singly-charged CQDs lower the energy...