胶体量子点垂直腔面发射激光器的设计与仿真
摘要
Objective: Featuring wide bandgap tunability, high quantum efficiency, and cost-efficient solution processible fabrication methods, colloidal quantum dots (QDs) have been studied and applied in various optoelectronic devices including photo detectors, light-emitting diodes (LEDs), and solar cells. In addition to applications based on the absorption and spontaneous emission of colloidal QDs, their stimulated emission potential has attracted extensive research interests, aiming toward a landmark target: the realization of the colloidal QD laser diodes. In the study of colloidal QD lasers, different laser architectures have been demonstrated, including Fabry-Perot cavity, distributed feedback laser cavity, whispering gallery mode cavity, and photonic crystal microcavity. The optical gain has been successfully realized in colloidal QDs under direct current pumping, demonstrating a major progress toward electrically pumped colloidal QD lasers. Furthermore, a dual function device based on specially engineered QDs that can function as an optically pumped laser and an LED is fabricated and characterized, revealing a promising pathway for realizing colloidal QD laser diodes. Different from edge-emitting lasers, vertical-cavity surface-emitting lasers exhibiting surface-emitting properties, wafer-level fabrication & characterization capability, and array integration ability have been widely used in optical fiber communication, laser printers, computer mouse, and three-dimensional facial recognition fields, etc. Here, we propose and design a colloidal quantum dots vertical cavity surface emitting laser, combining with a quantum dots light-emitting diode like current injection structure to realize the electroluminescence ability. Methods: As shown in Fig. 1, the QLED-like structure containing the QD gain medium is sandwiched by two high-reflective distributed feedback reflectors to form a vertical-cavity surface-emitting laser(VCSEL)-like device. The device is designed to w