Difference between ASE and stimulated emission

Click For Summary
SUMMARY

Amplified Spontaneous Emission (ASE) and stimulated emission are distinct phenomena in laser physics. While stimulated emission serves as the fundamental mechanism for both processes, ASE occurs when spontaneously emitted photons stimulate further emissions in a broadband manner, which is undesirable in laser operation. The key difference lies in the nature of the seeding photons; in stimulated emission, photons are directed into a specific narrow cavity mode, while ASE results from photons decaying into non-lasing modes, leading to noise and power loss in the desired frequency range.

PREREQUISITES
  • Understanding of laser physics principles
  • Familiarity with photon behavior and emission processes
  • Knowledge of optical cavity design and functionality
  • Basic concepts of light amplification and noise in lasers
NEXT STEPS
  • Research the principles of laser cavity design and its impact on emission types
  • Study the effects of ASE on laser performance and methods to mitigate it
  • Explore the role of photon statistics in stimulated emission versus ASE
  • Learn about different types of lasers and their susceptibility to ASE
USEFUL FOR

Physicists, optical engineers, and anyone involved in laser technology or research, particularly those focused on improving laser efficiency and performance.

TheCanadian
Messages
361
Reaction score
13
Is there any inherent difference between amplified spontaneous emission and stimulated emission? Is not stimulated emission simply the mechanism by which ASE occurs? Is stimulated emission just a broader term? I've read the two terms in literature and just wanted to ensure I understood the subtle differences between them.
 
They are both in principle stimulated emission yes, but the seeding photons are different. What you want in a laser is that all photons in the inverted population gets stimulated down into the specific narrow cavity mode that your mirrors define. However if a photon, for example, spontaneously decays into a mode other than the lasing one it also has a chance of causing further decay through the stimulated process. This is what is called ASE, and it's generally considered bad because it drains power from the narrow frequency mode you want your laser to have and puts it into the broadband (and also undirectional) ASE, essentially acting as noise around your main laser peak.
 

Similar threads

Graduate LASERs: Why is population inversion required for amplification?
  • · Replies 3 ·
Replies
3
Views
7K
High School Laser Production: Uncovering the Science and Processes Behind It
  • · Replies 11 ·
Replies
11
Views
3K
Undergrad Qualitative description of stimulated emission & population inversion
  • · Replies 18 ·
Replies
18
Views
2K
Undergrad Relation between blackbody radiation and spontaneous emission
  • · Replies 6 ·
Replies
6
Views
3K
Undergrad Understanding Lasers: Questions and Answers
  • · Replies 3 ·
Replies
3
Views
4K
Undergrad What's the interval between photons in stimulated emission?
  • · Replies 2 ·
Replies
2
Views
2K
Graduate Faraday Rotator: Optics for Amplifying Laser Light
  • · Replies 5 ·
Replies
5
Views
2K
Graduate Stimulated emission/absorption - which equations act on external targets?
  • · Replies 2 ·
Replies
2
Views
2K
Graduate Semi-classical argument for stimulated emission?
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad Ratio between spontaneous/stimulated emission
  • · Replies 1 ·
Replies
1
Views
13K