- A method for measuring the (dis)charging dynamics of organic semiconductors with single-electron resolution in multiple environments is developed using optical tweezers. A 1μm silica bead was coated with either a pristine organic semiconductor or an electron donor-acceptor blend, trapped using optical tweezers, and driven with an oscillating electrical driving force. The charge of the bead was measured simultaneously with the photoluminescence of the organic semiconductor coating. Uncoated silica spheres in water showed surface charges at least an order of magnitude greater than uncoated spheres in nonpolar toluene. Coated spheres showed charges smaller than uncoated spheres in both cases. The minimal interaction of the semiconductor coatings with the environment provides support for the use of optical tweezers in measuring the charge and change of charge of microscopic particles with resolution as good as a single electron, depending on the environment of the particle.
- Keywords: Organic, Semiconductor, Optical, Tweezers, Charge, Transfer