Influence of the shell geometry on the state of charge of CdSe/CdS dot-in-rods nanonocrystals

Colloidal nanocrystals (Ncs), quantum dots synthesized by means of wet-chemistry, can emit non-classical light at room temperature. In particular, CdSe/CdS dot-in-rods (DRs) with a spherical core and rod like shell have shown linearly polarized single photon emission [1]. A drawback of colloidal nanocrystals as light sources was the phenomenon known as blinking, i.e. photoluminescence fluctuations from ON to OFF periods. It has recently been solved in spherical ‘giant’ Ncs by growing thicker shells around the core [2]. However this was at the expense of their single photon emission properties. We have recently shown non-blinking behaviour in DRs while keeping single photon emission property by carefully engineering the shell thickness and length [3].