The relationship between photoluminescence (PL) intensity and absorption intensity is known as the photoluminescence quantum yield (PLQY). This measures the efficiency of a material to convert absorbed light into emitted light. In most cases, a higher absorption intensity leads to a higher PL intensity, indicating a higher PLQY.
There are several factors that can affect the relationship between PL intensity and absorption intensity, such as the composition and structure of the material, the excitation energy, and the presence of impurities or defects. Additionally, external factors like temperature and pressure can also influence this relationship.
Yes, the PLQY can be manipulated by changing the material's properties or by using external stimuli. For example, the PLQY can be increased by optimizing the material's composition and structure, or by introducing energy transfer processes. Alternatively, the PLQY can be decreased by introducing quenching species or by using high excitation energies.
The PLQY can be indirectly measured by comparing the PL intensity of a sample to a known standard with a known PLQY. Alternatively, it can be directly measured using specialized equipment such as a fluorometer or a spectrophotometer. These instruments can measure the absorption and emission spectra of a material, which can then be used to calculate the PLQY.
Understanding the relationship between PL intensity and absorption intensity is crucial in the design and optimization of photonic and optoelectronic devices. This knowledge can also be applied in fields such as solar energy conversion, biological imaging, and quantum technologies. By manipulating the PLQY, researchers can improve the efficiency and performance of these devices, leading to practical applications in various industries.