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The photoelectric effect is the emission of electrons from a material caused by electromagnetic radiation such as ultraviolet light. Electrons emitted in this manner are called photoelectrons. The phenomenon is studied in condensed matter physics, solid state, and quantum chemistry to draw inferences about the properties of atoms, molecules and ...
In batteries, the cut-off (final) voltage is the prescribed lower-limit voltage at which battery discharge is considered complete. The cut-off voltage is usually chosen so that the maximum useful capacity of the battery is achieved. The cut-off voltage is different from one battery to the other and it is highly dependent on the type of battery ...
Photocurrent is the electric current through a photosensitive device, such as a photodiode, as the result of exposure to radiant power. The photocurrent may occur as a result of the photoelectric, photoemissive, or photovoltaic effect. The photocurrent may be enhanced by internal gain caused by interaction among ions and photons under the ...
Historically, the photoelectric effect is associated with Albert Einstein, who relied upon the phenomenon to establish the fundamental principle of quantum mechanics in 1905, [4] an accomplishment for which Einstein received the 1921 Nobel Prize. It is worthwhile to note that Heinrich Hertz, working 18 years earlier, had not recognized that the ...
Photovoltaic effect. The photovoltaic effect is the generation of voltage and electric current in a material upon exposure to light. It is a physical phenomenon. [1] The photovoltaic effect is closely related to the photoelectric effect. For both phenomena, light is absorbed, causing excitation of an electron or other charge carrier to a higher ...
Photoemission electron microscopy (PEEM, also called photoelectron microscopy, PEM) is a type of electron microscopy that utilizes local variations in electron emission to generate image contrast. [citation needed] The excitation is usually produced by ultraviolet light, synchrotron radiation or X-ray sources.
The latter tends to increase solar cell output voltage while the former acts to erode it. The net effect, therefore, is a combination of the increase in voltage shown for increasing n in the figure to the right and the decrease in voltage shown for increasing I 0 in the figure above.
Photoionization. Photoionization is the physical process in which an incident photon ejects one or more electrons from an atom, ion or molecule. This is essentially the same process that occurs with the photoelectric effect with metals. In the case of a gas or single atoms, the term photoionization is more common.