Researchers at Los Alamos National Laboratory have made significant strides in advancing colloidal quantum dot technology for high-intensity light emitters, moving closer to the development of device-ready quantum dot laser diodes. Their dual-function devices can operate as both optically excited lasers and electrically driven LEDs, achieving brightness levels exceeding one million candela per square meter. This breakthrough has implications across various sectors, such as integrated electronics, photonics, and medical diagnostics.
The team has created a new type of quantum dot known as "compact compositionally graded quantum dots," which minimizes Auger recombination while maintaining a high gain coefficient. These advancements address previous challenges in achieving electrical pumping necessary for lasing, including optimizing charge injection architecture and minimizing optical losses. New designs, like the integration of a periodic grating as a feedback resonator, facilitate light amplification.
While the devices currently achieve lasing through optical excitation, overcoming heat-related performance issues during electrical pumping remains a crucial final challenge. The researchers’ work demonstrates practical solutions to notable problems that had previously hindered the development of electrically driven colloidal quantum dot lasers. Their results, published in Advanced Materials, signal a promising future for these devices.
