Researchers from RIKEN, the University of California, San Diego and others have developed a new mechanism to enhance the efficiency of OLED devices. The basic idea is to manipulate the electron spin to control the OLED exciton formation - basically lowering the OLED voltage so that only triplets and formed instead of a combination of singlets and triplets.
The researchers demonstrated this principal using an organic molecule called 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA), placed on a metal-supported, ultrathin insulating film. By measuring the emission spectrum, they could monitor the exciton type - and show that at a low voltage, only triplets are formed.
In 2013 we reported on the development of a bi-polar spin valve device that emits light - a so called SPIN-OLED device which could be a related design.