This chromium both gives a ruby its red color and also enables a ruby to undergo a population inversion and act as a laser.
22.
However, the actual invention of the maser ( and laser ) many years later was dependent on a method to produce a population inversion.
23.
Some of the light produced by the lamps is captured in the glass, leading to a population inversion that allows for amplification via stimulated emission.
24.
Technically, the encoding effect proceeds by the creation of a population inversion between the valence and conduction bands, with the resulting creation of plasmons.
25.
To create a population inversion under these conditions, it is necessary to selectively remove some atoms or molecules from the system based on differences in properties.
26.
This is important, since any appreciable population accumulating in level 3, the upper laser level, will form a population inversion with respect to level 2.
27.
The pulse sequence of INEPT, as shown in the diagram, can be read as a combination of spin echo and selective population inversion ( SPI ).
28.
These gain media could release stimulated emissions between an excited state and a lower excited state, not the ground state, facilitating the maintenance of a population inversion.
29.
Because at least half the population of atoms must be excited from the ground state to obtain a population inversion, the laser medium must be very strongly pumped.
30.
The population inversion in hydroxyl molecules is produced by far infrared radiation that results from absorption and re-emission of light from forming stars by surrounding interstellar dust.
