Exciton polaritons are hybrid particles that combine light and molecules of organic material, making them ideal vessels for energy transfer in organic semiconductors. Thanks to their photonic origins, they are both compatible with modern electronics and move speedily. However, they are difficult to control, and much of their behavior is a mystery.
Researchers have found a way to tune the speed of this energy flow. This “throttle” can move exciton polaritons from a near standstill to something approaching the speed of light and increase their range – an approach that could eventually lead to more efficient solar cells, sensors, and LEDs.
The researchers used a series of laser pulses that functioned like an ultrafast video camera to measure how energy moved within the microcavity structures in real-time. But the team hit a speedbump of their own. Polaritons are so complex that even interpreting such measurements can be arduous. The researchers were able to turbocharge the polaritons by incorporating more mirrors and increasing the reflectivity in the microcavity resonator.
Many technologies that use exciton polaritons rather than electrons only operate at cryogenic temperatures. But with organic semiconductors, you can start to achieve a lot of interesting, exciting functionality at room temperature. So, these same phenomena can feed into new kinds of lasers, quantum simulators, or computers, even.