In OPN’s December “Optics in 2023” review of interesting research, researchers from Tsinghua University, China, offered a look at their new 3D-nanoprinting technique, photoexcitation-induced chemical bonding, which uses femtosecond laser pulses to directly assemble and print colloidal nanocrystals (quantum dots) into 3D nanostructures. The researchers believe the method will “open new avenues in the manufacturing of freeform 3D nanophotonic and optoelectronic devices” This video provides an overview of the process.