RP Photonics

Encyclopedia … combined with a great Buyer's Guide!

VLib
Virtual
Library

Pump Parameter

<<<  |  >>>

Definition: the ratio of pump power and threshold pump power of a laser

German: Pumpparameter

Category: lasers

Units: (dimensionless number)

How to cite the article; suggest additional literature

The pump parameter r of a laser is the ratio of pump power and threshold pump power. Usually, this quantity is used for optically pumped lasers.

Most lasers are operated with a pump parameter between 3 and 10, i.e. significantly but not very far above threshold. This is because extreme values often have some disadvantages:

Extreme values of pump parameters are nevertheless required in some cases:

Particularly in the context of four-level lasers, it can be convenient to use the pump parameter r in equations, as it is most easy to evaluate in an experiment, and thus often well known. In four-level lasers, the intracavity optical intensity in the gain medium (in the steady state, assuming a flat-top mode profile) is (r − 1) times the saturation intensity. Also, there is a simple equation for the frequency of relaxation oscillations, containing the parameter r. However, such equations then often do not hold for (quasi-)three-level gain media.

See also: threshold pump power, lasers, relaxation oscillations, four-level and three-level gain media, Spotlight article 2007-01-21
and other articles in the category lasers

If you like this article, share it with your friends and colleagues, e.g. via social media:

arrow