Low Pressure Band Tuning in Wurtzite CdSe Quantum Dots

Several studies to date have probed structural phase transitions in quantum dots (QDs) at high pressure. At low pressure (< 1 GPa), the optical properties of solvated nanomaterials are modulated by pressure induced electronic level tuning, particularly for surface and trap states. In fact, low pressure studies on solvated CdSe QDs may provide insight into the participation of surface hole traps and electron traps on the excited state optical properties in these materials. We report findings of QD size dependent pressure coefficients and postulate that trap state tuning, surface reconstruction events, and electron-hole exchange interactions may play a role in the low-pressure regime.