All Questions
Tagged with quantum-electrodynamics optics
81
questions
3
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2
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105
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Parametric down-conversion - QFT necessary?
In quantum optics, one ususally starts by quantizing the free electric field and obtains an expression for the electric field operators:
$$ E(\vec{r},t) = \sum_{\vec{k},p} C_{\vec{k}} \vec{e}_{\vec{k},...
- 31
1
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2
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108
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How is light interference explained with photons?
In the classical model of light as an EM wave, interference is a trivial consequence of the linearity of the wave equation. Now, if we model light as collections of photons, how is light interference ...
- 1,775
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1
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57
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Interferometer designed to create diffraction in free space
I designed the following interferometer:
If the light beam -theoretically- is very narrow , will light be diffracted away from point B from QED's perspective?
- 81
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Feynman trajectories of a photon from entangled pair
In a pair of Entangled photons does any of the two photons has the Feynman trajectories of the other one? Must the possible trajectories of photon 2 be taken in the Feynman's path integral for the ...
- 651
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QFT view of lower light speed of light in medium [duplicate]
In classical EM theory, if we have a medium whose dielectric coefficient is independent of wavelengths (suppose we filter the incoming signal to a certain frequency band), then the waveform gets to ...
0
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0
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38
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Microscopic explanation of electromagnetic wave interacting with electron (medium) leading to decrease of light speed
Electromagnetic waves decrease in speed when propagating through a medium. The commonly accepted microscopic explanation is that photons are absorbed by electrons and then re-emitted, resulting in a ...
- 59
-1
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1
answer
66
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The enigma of photon behavior, photon spatial co-inhabitance
The notion that multiple photons can occupy the same spatial coordinates seems perplexing. How is this experimentally validated, considering the intricate challenges and oddities it presents?
Imagine ...
- 11
1
vote
1
answer
107
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Why would energy conservation be violated during interference if a wave function represented multiple photons?
the below paragraph is from Paul Dirac's 'The principles of quantum mechanics'. He argues that representing multiple photons' probability distribution via a single wavefunction leads to energy ...
- 301
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2
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117
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On the level of Newton's particle theory of light
Huygens and Maxwell have wave theories about light.
On the other hand Planck and Einstein have theories about particle nature of light and could explain blackbody radiation and photoelectric effect ...
- 1,409
1
vote
1
answer
90
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Feynman Diagrams for Spontaneous Parametric Down Conversion
Nonlinear optical process called the 'Spontaneous Parametric Down Conversion' (SPDC) divides a photon of high frequency into two photons of lower frequencies with energy conservation. But I see no ...
- 57
0
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1
answer
170
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dB of squeezed light is equivalent to how much squeezing in different directions?
In many structures, the amount of squeezed light is expressed in dB. I wanted to know what is meant by squeezed light in dB.
For example, 10 dB of squeezed light is equivalent to how much squeezing in ...
- 65
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votes
1
answer
175
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Do quasiphotons have mass?
If I understand correctly, per special relativity, anything that travels at a speed of $c$ must be massless and conversely, anything massless must travel at precisely $c$ in akl reference frame. We ...
- 2,327
16
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6
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Is interference of light a quantum phenomenon?
I am wondering whether the light interference is a quantum phenomenon. Or, alternatively, is there any interference in Maxwell's theory understood as a classical field theory?
The reason I am puzzled ...
- 705
0
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0
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57
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How to interpret light and photon?
I've been trying to solidify my understanding on properties of light and this is what my understanding is so far:
Light is an EM wave that travels in a constant speed C.
Light has a quantized energy ...
- 275
8
votes
1
answer
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Why is it that, when light travels in a medium, we say it's made of "quasiparticles"?
I get why, in this model, light isn't really "made of" photons, because photons, by definition have zero mass and travel at $c$, whereas these quasiparticles, if I understand correctly, do ...
- 2,327