There are several synonyms for the term "IQE" which stands for "Internal Quantum Efficiency". Some of the synonyms include "efficiency of light emission", "quantum efficiency", "intrinsic quantum yield". These terms all refer to the same concept and describe the ability of a material to convert absorbed energy into light. IQE is a crucial parameter used in the field of solid-state lighting and device engineering. It is measured by comparing the number of photons emitted by a material to the number of photons absorbed. The higher the IQE, the more efficient the material is at emitting light. These synonyms are frequently used in scientific literature and are important for understanding the performance of light-emitting devices.