CAREER: Novel Nanomaterials for Scalable Entangled Photon Emitters

This CAREER award is jointly funded by the Electronic and Photonic Materials Program (EPM) in the Division of Materials Research (DMR), and by the Electronics, Photonics, and Magnetic Devices Program (EPMD) in the Division of Electrical, Communications and Cyber Systems (ECCS). Nontechnical Description: The research goal of this CAREER award is to develop novel nanomaterials that may one day transform computing power and data security. To achieve these outcomes, one strategy relies on a peculiar property called quantum entanglement. According to quantum mechanics, two entangled photons remain "linked" together, even when separated by a large distance. A change to one of the two photons instantaneously affects the other. To help revolutionize computing and cryptography, efficient sources of entangled photons are needed. The research component of this CAREER award is to develop a new type of quantum dot for efficiently generating entangled photons. The research efforts are integrated with educational activities benefiting graduate and undergraduate student researchers who are learning cutting edge techniques to synthesize nanomaterials, measure their physical properties, and fabricate test devices. Educational outreach activities, involving undergraduate researchers, grade 4-6 students and the general public enhance Idaho's workforce diversity in science, technology, engineering and math fields, while also increasing undergraduate retention. Technical Description: Researchers have long proposed using quantum dots as the basis for compact, electrically driven entangled photon sources. However, traditional quantum dots are prone to large fine structure splitting between exciton states, preventing robust photon entanglement. The research project addresses this issue by introducing a novel technique for synthesizing self-assembled quantum dots on semiconductor surfaces with specific orientations. These new quantum dots are not expected to suffer from fine structure splitting and should hence be ideal entangled photon sources. The project aims to explore quantum dot nucleation and growth at the atomic level; to study quantum dot synthesis-structure-property relations; to demonstrate photon entanglement; to investigate fiber-compatible entangled photons; and to fabricate proof-of-concept devices.