Creating dream materials with semiconductor quantum dots that can behave like metal, which can provide new materials and -Attractive to this popular class. Researchers at the RIKEN Center for Emergent Matter Science and their collaborators have succeeded in creating a “superlattice” of semiconductor quantum dots.
Semiconductor colloidal quantum dots have attracted much research interest due to their unique optical properties, which result from the quantum confinement effect. They are used in solar cells, where they can improve conversion efficiency, biological imaging, where they can be used as fluorescent probes, electronic displays, and even quantum computers, where their ability to trap and manipulate electrons individually.
However, getting semiconductor quantum dots to conduct electricity efficiently has been a major challenge, preventing their full use. This is mainly due to their lack of guidance and assembly. According to research leader Satria Zulkarnaen Bisri, who conducted the research at RIKEN and currently works at the Tokyo University of Agriculture and Technology, “improving them will allow, for example, quantum dot displays brighter while using less energy than current devices.
Now the team has published a study in Nature Communications that can help a lot to achieve this goal. The team, led by Bisri and Yoshihiro Iwasa of RIKEN CEMS, developed large-scale lead sulfide semiconductor colloidal quantum dots that exhibit the electrical control properties of metals.
The key to doing this is getting the quantum dots in order to connect to each other directly, “epitaxially,” without ligands, and to do so with their faces aligned.
The researchers tested the conductivity of their invention, and by increasing the density of the carrier using a double electric transistor, they found that at one time it became a million times more than the current and quantum dot display. . Importantly, the quantum confinement of individual quantum dots is maintained, meaning that they do not lose their functionality despite high conductivity.
“Semiconductor quantum dots have shown promise for their optical properties, but their electron mobility has been a challenge,” Iwasa said. “Our research has shown that precise control of the orientation of quantum dots and assemblies can lead to high electron mobility and metallic properties. This breakthrough could open new avenues for using semiconductor quantum dots in emerging technologies.”
According to Bisri, “We plan to use this class of material to conduct further studies and believe that this can lead to significant improvements in the capabilities of quantum dot superlattices. In addition to improving the current device, which this can lead to new applications such as perfect QD devices, electrical devices, thermoelectric devices, and critical detectors and sensors, which have not yet exceeded the quantum dot limit.
Source: RIKEN
