Do Photons from White Light Emit Randomly with Specific Lifespans?

  • Thread starter Thread starter coke
  • Start date Start date
  • Tags Tags
    Photon
Click For Summary
SUMMARY

The discussion centers on the emission characteristics of photons from white light sources, specifically addressing the timing and lifespan of photon emissions. It is established that while photons are emitted in bursts, the coherence time of broadband visible light is approximately 1 nanosecond (ns), which differs from the actual existence time of the photons. The emission of photons does not occur at regular intervals; rather, it is influenced by the energy output of the light source, such as a 0.1 W bulb emitting light at a wavelength of 0.5 microns. The concept of coherence time is crucial for understanding the predictability of the light field over short durations.

PREREQUISITES
  • Understanding of photon emission and wave packets
  • Knowledge of coherence time in optics
  • Familiarity with energy output calculations for light sources
  • Basic principles of visible light wavelengths
NEXT STEPS
  • Research the concept of coherence time in different light sources
  • Learn about photon production rates based on energy output
  • Explore the differences between coherence time and existence time of photons
  • Investigate the implications of photon emission timing on optical technologies
USEFUL FOR

Physicists, optical engineers, and anyone interested in the properties of light and photon behavior in various applications.

coke
Messages
8
Reaction score
0
hi, as we know, lamp emits light not continuously but in 'burst', which we may call wave packet or photon. my question is,
1. Is it emitted one photon by one photon with random time delay ?
2. it is said that the duration time of the photon from white light is about 10^-9 sec(nanosecond), does it mean that each photon lasts for 10^-9 sec ?
3. if the above two questions are both correct, then does it mean that 10^-9 sec late after the emission of the first photon, wait an unpredictable time later, another photon emitted ? then how about the first one ? where does it go ? die out ?

can anyone help ? thank you so much !
 
Physics news on Phys.org
In brief,

1) You can calculate the rate of photon production by energy- say 0.1 W of visible light is emitted from a bulb, assume 0.5 microns for a wavelength.

2) That's not correct- the 'coherence time' of broadband visible light can be around 1 ns. That is different from 'existence time'. Coherence means how predictable the field is in the future, given current knowledge of it- for broadband visible light, I can predict the value about 1 ns in advance.
 

Similar threads

Replies
15
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 38 ·
2
Replies
38
Views
7K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
5K
Replies
3
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
2
Views
11K
  • · Replies 8 ·
Replies
8
Views
1K
Replies
11
Views
3K