Photoluminescence is a process where a material absorbs photons and then re-emits them. In nanotechnology, materials like quantum dots are often used due to their unique optical properties. When these nanomaterials absorb light, electrons are excited to a higher energy state. When these electrons return to their ground state, they emit photons, resulting in light emission. The wavelength of the emitted light can be precisely controlled by adjusting the size of the quantum dots.
