Stimulated Emission & Emitted photon direction

Click For Summary
SUMMARY

The discussion centers on the phenomenon of stimulated emission, where a photon of the correct wavelength causes an electron to transition from a higher to a lower energy level, resulting in the emission of a new photon that matches the original in wavelength, phase, and direction. This process is governed by Einstein's coefficients, specifically the symmetry between absorption and stimulated emission. The conversation also explores the implications of radiation pressure, suggesting a theoretical framework for considering stimulated emission through negative radiation pressure, which could influence photon behavior in specific directions.

PREREQUISITES
  • Understanding of quantum mechanics principles, particularly photon-electron interactions.
  • Familiarity with Einstein's coefficients and their role in absorption and emission processes.
  • Knowledge of stimulated emission and its applications in laser technology.
  • Basic concepts of radiation pressure and its effects on photon dynamics.
NEXT STEPS
  • Research the principles of stimulated emission in laser physics.
  • Study Einstein's coefficients and their significance in quantum transitions.
  • Explore the concept of radiation pressure and its implications in optics.
  • Investigate the theoretical framework of negative radiation pressure and its potential effects on photon behavior.
USEFUL FOR

Physicists, optical engineers, and students of quantum mechanics interested in the principles of laser operation and photon dynamics.

RobbyQ
Messages
32
Reaction score
11
TL;DR
Stimulated Emission & Emitted photon direction
I always understood that a photon of correct wavelength would raise the energy level of an electron (which is the case)
But reading about lasers and stimulated emission I read the following where the electron drops a level upon absorption:-
"A photon with the correct wavelength to be absorbed by a transition can also cause an electron to drop from the higher to the lower level, emitting a new photon. The emitted photon exactly matches the original photon in wavelength, phase, and direction. This process is called stimulated emission."

How is this possible i.e dropping to a lower energy level and how/why is the photon wavelength, phase, and direction preserved?
 
Science news on Phys.org
Stimulated emission-absorption equations would be exchanged if performing CPT symmetry, suggesting they are CPT analogs - also through B_{12}=B_{21} symmetry for their Einstein's coefficients.

If so, and absorption is from positive radiation pressure, pushing photons into a target (from given direction) ... maybe we should think about stimulated emission through negative radiation pressure, pulling of photons (in given direction)?
https://scholar.google.pl/scholar?q=negative+radiation+pressure
https://www.physicsforums.com/threads/negative-radiation-pressure.1053657/
 
Last edited:

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 18 ·
Replies
18
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 21 ·
Replies
21
Views
1K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
11
Views
2K
  • · Replies 4 ·
Replies
4
Views
1K