Shape-Controlled HgTe Colloidal Quantum Dots and Reduced Spin–Orbit Splitting in the Tetrahedral Shape

Spherical and tetrahedral HgTe colloidal quantum dots (CQDs) are synthesized, and their doping is tuned electrochemically. Compared to spherical dots of a similar volume, the tetrahedral CQDs show a decrease in confinement energy as well as a sharper band edge absorption. The intraband spectra of the tetrahedral CQDs also display a smaller splitting from spin–orbit coupling. The shape-controlled synthesis with an improved size distribution and sharper optical features could find applications in optoelectronic devices.