Researchers from the University of Cambridge and the Eindhoven University of Technology have developed an organic semiconductor that forces electrons to spiral like a corkscrew. In doing so, the device could lead to brighter, more energy-efficient screens and even pave the way for next-generation computing.
The setup hinges on a phenomenon called chirality, a property often found in nature but rarely harnessed in electronics. Chirality refers to structures that are mirror images of each other, like left and right hands. While most inorganic semiconductors, such as silicon, are symmetrical, the new semiconductor is designed to be chiral, guiding electrons in a spiral motion and emitting light with a specific “handedness.”
Spiral Light
The semiconductor material is called triazatruxene (TAT). What’s intriguing is its ability to self-assemble into helical stacks. Imagine a spiral staircase at the molecular level, with electrons whirling around like dancers on a twisting stage. When excited by blue or ultraviolet light, these spiraling electrons emit bright green light with a strong circular polarization—a property that has been notoriously difficult to achieve in semiconductors.
“The structure of TAT allows electrons to move efficiently while affecting how light is emitted,” said Marco Preuss, a co-first author of the study from the Eindhoven University of Technology.
The research builds on decades of collaboration between the research groups of Professor Sir Richard Friend at Cambridge and Professor Bert Meijer at Eindhoven. “This is a real breakthrough in making a chiral semiconductor,” said Meijer. “By carefully designing the molecular structure, we’ve coupled the chirality of the structure to the motion of the electrons, and that’s never been done at this level before.”
From the Lab to the Living Room
The most immediate application of this technology is in display screens. Current OLED displays in televisions and smartphones waste a significant amount of energy because they rely on filters to control the light emitted. The new chiral semiconductor naturally emits polarized light, so you wouldn’t need these filters while making screens brighter and more energy-efficient.
In one experiment, the TAT was incorporated into circularly polarized OLEDs (CP-OLEDs). These devices achieved record-breaking efficiency, brightness, and polarization levels.
“We’ve essentially reworked the standard recipe for making OLEDs like we have in our smartphones, allowing us to trap a chiral structure within a stable, non-crystallising matrix,” said Rituparno Chowdhury, a co-first author from Cambridge’s Cavendish Laboratory. “This provides a practical way to create circularly polarised LEDs, something that has long eluded the field.”
But the implications go far beyond screens. The ability to control the spin and motion of electrons opens up exciting possibilities for quantum computing and spintronics, fields that aim to harness the inherent angular momentum of electrons to store and process information.
Organic semiconductors were once dismissed as impractical, but now underpin a $60 billion industry, thanks to their flexibility and versatility.
“When I started working with organic semiconductors, many people doubted their potential, but now they dominate display technology,” said Friend. “Unlike rigid inorganic semiconductors, molecular materials offer incredible flexibility—allowing us to design entirely new structures, like chiral LEDs. It’s like working with a Lego set with every kind of shape you can imagine, rather than just rectangular bricks.”
The findings appeared in the journal Science.
