Physics · Optics, Nature of Light and Optical Instruments

Optical pumping suggests that the method of creating an inverted population is called optical pumping. Optical pumping is a technique where the laser material is illuminated with light to excite the atoms or molecules, causing them to populate higher energy levels. This population inversion is necessary for the operation of a laser.  

This option suggests that the method of creating an inverted population is called optical pumping. Optical pumping is a technique where the laser material is illuminated with light to excite the atoms or molecules, causing them to populate higher energy levels. This population inversion is necessary for the operation of a laser.

This option suggests that the method of creating an inverted population is called excitation. Excitation refers to the process of promoting an atom or molecule from a lower energy state to a higher energy state. While excitation is involved in the process of creating an inverted population, it is not the specific method or technique used. 

This option refers to a different phenomenon unrelated to creating an inverted population. Bremsstrahlung is the emission of electromagnetic radiation (usually X-rays or gamma rays) when a charged particle, such as an electron, is decelerated or deflected by another charged particle or a nucleus. 

This option refers to a different technique used for creating three-dimensional images called holograms. Holography involves the use of interference patterns recorded on photographic plates or other media to reconstruct a three-dimensional image when illuminated with coherent light.