RP Photonics logo
RP Photonics
Encyclopedia
Consulting Software Encyclopedia Buyer's Guide

Short address: rpp-con.com

Dr. Paschotta, the founder of RP Photonics, supports your R & D with his deep expertise. Save time and money with efficient support!

Short address: rpp-soft.com

Powerful simulation software for fiber lasers and amplifiers, resonator design, pulse propagation and multilayer coating design.

Short address: rpp-enc.com

The famous Encyclopedia of Laser Physics and Technology provides a wealth of high-quality scientific and technical information.

Short address: rpp-bg.com

In the RP Photonics Buyer's Guide, you easily find suppliers for photo­nics products. As a supp­lier, you can profit from enhanced entries!

Learn on lasers and photonics every day!
VL logo part of the
Virtual
Library

Self-terminating Laser Transitions

<<<  |  >>>  |  Feedback

Buyer's Guide

Use the RP Photonics Buyer's Guide to find suppliers for photonics products! You will hardly find a more convenient resource.

Ask RP Photonics for any advice concerning details of solid-state gain media. If required, RP Photonics can offer advanced modeling.

Definition: laser transitions which can not be continuously operated due to the accumulation of population in the lower laser level

Category: lasers

How to cite the article

Some solid-state gain media have laser transitions where the lower laser level is metastable and has a long lifetime – even longer than the upper-state lifetime. An example of this situation is the 2.7-μm transition (4I11/2 → 4I13/2) of erbium (Er3+) in fluoride fibers. Here, neither multi-phonon transitions nor the pump radiation can depopulate the lower laser level. In that case, the laser transition is usually self-terminating: lasing is possible only for a short while, until the lower level is so strongly populated that a population inversion is no longer possible. After that, the gain medium requires some time without pumping, until lasing can be restarted.

Sometimes it is possible to cure that problem with some additional dopant which can quench the population of the lower laser level by means of an energy transfer. In the above-mentioned case, praseodymium (Pr3+) codoping has proven to be a good solution [2, 3]. An alternative, but less successful solution is to use a high erbium doping concentration [1]. This introduces various cross-relaxation processes, which can depopulate the lower laser level but also affect the upper-state population. Also, it is sometimes possible to arrange for cooperative lasing from the lower laser level to a still lower energy level.

Bibliography

[1]E. Poppe et al., “980 nm diode-pumped continuous wave mid-IR (2.7 μm) fiber laser”, Electron. Lett. 34, 2331 (1998)
[2]B. Srinivasan et al., “High-power 'watt-level' CW operation of diode-pumped 2.7 μm fiber lasers using efficient cross-relaxation and energy transfer mechanisms”, Opt. Express 4 (12), 490 (1999)
[3]S. D. Jackson et al., “Diode-pumped 1.7-W erbium 3-μm fiber laser”, Opt. Lett. 24 (16), 1133 (1999)

See also: laser transitions, lower-state lifetime, upper-state lifetime, cooperative lasing, quenching, gain media, solid-state lasers

How do you rate this article?

Your general impression: don't know poor satisfactory good excellent
Technical quality: don't know poor satisfactory good excellent
Usefulness: don't know poor satisfactory good excellent
Readability: don't know poor satisfactory good excellent
Comments:

Found any errors? Suggestions for improvements? Do you know a better web page on this topic?

Spam protection: (enter the value of 5 + 8 in this field!)

If you want a response, you may leave your e-mail address in the comments field, or directly send an e-mail.

If you like our website, you may also want to get our newsletters!

arrow

Fiber Optics Software

RP Fiber Calculator software

RP Fiber Calculator – a convenient tool for calculations on optical fibers:

mode profiles

screen shot

The basic version of this software is offered for free!

– Show all banners –

– Get your own banner! –