Elizabeth Coda Rose Hills
Investigating Molybdenum Disulfide Quantum Dot Blinking
Quantum dots are tiny, semiconducting particles with unique electronic properties that distinguish them from larger particles. Notably, quantum dots have discrete energy levels. Thus, by changing the size of the dot, the difference between these energy levels change. As the size of a quantum dot decreases, the energy difference increases between the highest and lowest bands. Thus, more energy is needed to excite the dot and more is released when it returns to its ground state. As a result, quantum dots can emit light of any frequency. Notably, two-dimensional transition metal dichalcogenides have been demonstrated to be made small enough to exhibit these properties. In particular, molybdenum disulfide exhibits interesting size dependent properties. My project this summer will investigate the dynamics of trapping and charging mechanisms of molybdenum disulfide quantum dots that cause fluorescent intermittency, known as quantum dot blinking, a phenomenon in which quantum dots turn their photoluminescence on and off. An understanding of these properties holds potential for diverse applications including in bioimaging, display devices, lasers, and sensors.