This population inversion arises for typically 100 femtoseconds during the " interaction of a slow "'highly charged ion "'( HCI ) with a solid surface ".
42.
As long as the intensity " I " ( " z " ) is small enough so that it does not have a significant effect on the magnitude of the population inversion.
43.
Until the late 1990s, when blue semiconductor lasers were developed, blue lasers were large and expensive gas laser instruments which relied on population inversion in rare gas mixtures and needed high currents and strong cooling.
44.
Some of this light is absorbed by the neodymium atoms in the glass, raising them to an excited state and leading to a population inversion which readies the lasing medium for amplification of a laser beam.
45.
:No . Without a mirror and partially silvered mirror, there is no resonance chamber to produce the population inversion necessary for laser light . talk ) 17 : 39, 12 September 2011 ( UTC)
46.
Laser science is principally concerned with quantum electronics, laser construction, optical cavity design, the physics of producing a population inversion in laser media, and the temporal evolution of the light field in the laser.
47.
This is the population inversion part of the scheme, where a further 90?pulse after a time period on both the sensitive and insensitive nuclei rotate the magnetization onto the " z "-axis.
48.
In 1957 he published a paper on the theory of a three-level maser, and his discovery of the stimulated Raman effect that a Stokes-shifted Raman transition can produce amplification without requiring a population inversion.
49.
A population inversion ( " N " 2 > " N " 1 ) has thus been achieved between level 1 and 2, and optical amplification at the frequency ? 21 can be obtained.
50.
Since only a few atoms must be excited into the upper laser level to form a population inversion, a four-level laser is much more efficient than a three-level one, and most practical lasers are of this type.
