Photoelectric effect introduction
The photoelectric effect is an important and magical phenomenon in physics. Under the irradiation of an electromagnetic wave higher than a certain frequency (this frequency is called the threshold frequency), the electrons inside certain substances absorb energy and escape to form a current, that is, photoelectricity.
The photoelectric phenomenon was discovered by the German physicist Hertz in 1887, and the correct interpretation was proposed by Einstein. In the process of studying the photoelectric effect, scientists have a deeper understanding of the quantum nature of photons, which has a major impact on the concept of wave-particle duality.