The primary steps of organic solar cells studied in a 0.4 K cold nanolaboratory

Almost all solar cells in use today and on the market are made of compounds containing Si. Their efficiency of converting solar energy to useful electrical energy suffers from a fundamental limit, which prevents the full exploitation of the energy from the sun.
One potential way to building more efficient solar cells is to use specific organic materials. These materials are able to absorb visible light, the spectral region containing most of the energy received from the sun, and to double the electrical current. The key to this doubling is a quantum mechanical process termed singlet fission, where a single molecule, excited by sunlight, shares its energy by another molecule nearby, and thereby doubles the number of charge carriers. The purpose of this project is to explore the fundamental mechanism of singlet fission, using ultrashort laser pulses and molecules embedded in nanometer-sized droplets of ultracold, superfluid helium.