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1answer
88 views

Spatial wave-function of a single photon and its measurement

In the last decade there were several papers claiming that they've measured a "transverse quantum state" / "quantum wave-function" / "spatial Wigner function" of a single photon: Measurement of the ...
0
votes
0answers
35 views

Explanation about light reflection in Feynman's QED

In his book QED, Feynman explained how the probability of light reflecting from a mirror can be calculated by summing unit vectors, with their direction representing the phase of the wavefunctions. ...
0
votes
1answer
35 views

What does 'coupling' mean? (Laser)

I assume this question is so basic that no YT-video or paper I found answers it. But in order to understand I have to know what it refers to. I'm talking about laser coupling to be exact. I have a '...
0
votes
0answers
15 views

How does photoluminescence spectroscopy work and how can it apply to quantum dots?

Does anyone have a clear explanation of how photoluminescence works? I know some of the basics, for example, that electrons are excited by photons to create excitons and when the excitons recombine, ...
3
votes
2answers
209 views

Fock states and beam splitters

A classical beam splitter divides incoming light into two parts according to the reflection and transmission coefficients. A quantum beam splitter on the other hand, can be modelled using Fock states,...
2
votes
1answer
83 views

Second order correlation function of a quantized electric field

I'm analysing an open quantum system where the optical cavity is interacting with a quantum dot. I modelled the system using cavity QED and used Lindblad master equation to model the system. Now I ...
1
vote
2answers
440 views

Photon spin and total angular momentun

I'm studying the photon spin and I assume that the angular momentum of spin is equal to 1 (from QED). In my book it's written, related to photons, that it doesn't make sense distinguishing between ...
2
votes
0answers
160 views

The Purcell effect, it's influence on the lifetime and quantum yield (of fluorophores)

So I've been looking into the Purcell effect and how it interacts with fluorophores (fluorescent molecules). The Purcell arises when you have a dipole in a cavity or even just near a dielectric or ...
1
vote
1answer
42 views

Why do two-photon interactions only occur at extremely high energies?

I've been reading for pleasure about two-photon interaction experiments, and one thing that confuses me is why, for example, two photons in the visible spectrum cannot interact. Is this indeed the ...
1
vote
0answers
64 views

Rigorous derivation of “reflection of light from mirror” from QFT

In the book "QED: The Strange Theory of Light and Matter" Feynman derives classical law of light reflection from mirror in a intuitive way from QED. but i want a more rigorous way from principles ...
0
votes
1answer
67 views

How does frequency mixing work in a non-linear crystal?

Current understanding: Nonlinear optics is classified by the effect of an electric field applied to a medium. In nonlinear crystals, when a field is applied the dielectric polarization does not ...
6
votes
4answers
762 views

What is the experimental evidence for a quantized EM field?

I've recently been trying to understand on a deeper level what is the physical meaning or existance of photons, and relatedly, what is the experimental verification of their existance. We all learn ...
1
vote
1answer
76 views

Full transmission of monochromatic light for a given thickness of glass

If you read the QED from Feynman he says that it is possible to get a 100% transmission of light for a specific thickness of glass. He explains the phenomenon perfectly but I don't know how to ...
1
vote
1answer
116 views

Why the excited states of an atom have an energy width?

All my experience with textbook problems of quantum mechanics shows that the energy levels associated with the bound states of a confined quantum system are discrete and sharp. For example, the energy ...
1
vote
2answers
147 views

Sending a single photon to glass

So as you can see in the image light is both refracted and reflected from the surface of glass. So what would happen if we only send a single photon. Would it refract or reflected. Would we be able to ...
1
vote
1answer
2k views

How is Hue, Saturation and Brightness of colours explained via EM and QED?

Light is a electromagnetic wave and its wavelengths determines the colour of the light, so that would be the Hue. But what determines the Saturation. The less saturated a colour is the more greyish ...
6
votes
4answers
999 views

Is reflection and refraction the same thing - bouncing of light?

I've been trying to wrap my head around what determines whether a ray of light is being reflected or refracted. A beam of light does both, as shown in this picture. http://sc663dcag.weebly.com/uploads/...
2
votes
1answer
110 views

Inverse pair production w/hohlaraum as photon target - is this experiment going to be carried out?

The IFLScience article Scientists Work Out How To Make Matter From Light describes photon-photon collisions producing pairs of particles, and the Nature Photonics Letter A photon–photon collider in a ...
2
votes
1answer
492 views

How is the reflection probability calculated?

I was reading Feynman's book on QED and I stumbled upon the probability of reflection of photons by a piece of glass. Is there a way to calculate the probabilty of reflection?
1
vote
2answers
290 views

Reading Q.E.D. by Richard Feynman, questions regarding speed of light at different colors

I have very recently begun reading Q.E.D. by Richard Feynman (I have no physics background, only learning concepts not mathematical models). In his example of light reflecting off of glass, he ...
3
votes
0answers
119 views

Physical interpretation of Glauber states [duplicate]

The definition of a Glauber, or coherent, state is $$a|\alpha\rangle = \alpha|\alpha\rangle.$$ Why is this a useful definition? Grynberg's Quantum Optics book simply says "a quasi-classical state $|...
0
votes
1answer
53 views

Gives light reflected on glass the only sine-waves?

If you put a light beam on glass some of the photons are reflected but the most of them will pass through the glass. Depending on the thickness of the glass light will be reflected from 0% till 16% ...
3
votes
1answer
193 views

Validity of the 'photon wavetrain' model of coherence

In some optics textbooks, coherence is introduced with the "photon wavetrain" model. In this model, we consider light generated by many atoms each making the same transition. During each transition, a ...
24
votes
1answer
1k views

How can my window not scramble the image of my yard?

How can an image pass through a window if the atoms in the glass randomly emit photons in any direction? I've read that glass is transparent because the atoms don't readily adsorb visible light, so it ...
17
votes
1answer
840 views

Stimulated Emission in QED

The explanations of stimulated emission which I have found all describe the phenomenon in terms of non-relativistic quantum mechanics. How might you describe it in a field theory such as QED? In ...
3
votes
3answers
372 views

Is Huygens's Wave Theory still correct?

We have to study on details about Huygens's Wave Theory though we have Electromagnetic theory, quantum theory today. Is it still correct or not?
2
votes
2answers
548 views

How light splits up into different colours when passed through prism using QED?

I want to know how light gets splits up into different colours when it is passed through prism? How light interacts with atoms and electrons of the prism? Can someone explain this to me using Quantum ...
0
votes
1answer
112 views

Can QED explain this or do I have revert to the classical model of light?

I want to know can QED can explain this image,like why there are someplaces with low light (shadows) like behind the chair, and why there are some places that are bright(rest of the floor). I know ...
0
votes
2answers
316 views

Is the glass made up of holes that let the light to go through it?

The following passage has been extracted from the book "The Magic of Science-A.Frederick Collins" (1917): Substances of all kinds have pores or holes in them. A sponge has pores that can be ...
0
votes
0answers
142 views

Is the image formed at the retina messy?

The following passage has been extracted from Newton's book Opticks: ...So if PR [in Fig.at the top] represent any Object without Doors, and AB be a Lens placed at a hole in the Window-shut of ...
2
votes
0answers
105 views

Expectation value for the time of a photon reflection

A photon is reflected by matter (by an electron in empty space). How long does the reflection take? (i.e. is there any infinitesimal time elapsing during the reflection process?), or more precisely, ...
5
votes
2answers
2k views

What is the difference between surface plasmon and surface plasmon polariton?

I'm trying to understand this reading article linked below and I still don't know how to explain this simply, without need to derive everything mathematically. Can someone just write here how do SP's ...
8
votes
1answer
216 views

How can results from classical optics be obtained from QFT?

Recently it came to my mind, that I have some basic knowledge about QFT and know im principle how to calculate scattering amplitudes (at least for the $\phi^4$-theory), but have no idea how to ...
1
vote
0answers
45 views

Do plasmons depend on the ambient EM field?

Imagine a situation: There's an illuminated metal slab in vacuum. Normally, there are some plasmons created running all over the slab. What would happen if we had turned a giant magnet near the slab? ...
2
votes
2answers
163 views

What is light localisation?

Reading about plasmonic nanoparticles I faced the term "localised light". How can one localise light? What are applications of it?
1
vote
1answer
2k views

Explanation of photon reflection [duplicate]

What occurs in atomic scale that cause the photon to be reflected? In other words, what is the reason for photons to change its direction and why material can reflect certain wavelengths and absorb ...
23
votes
4answers
13k views

Explain reflection laws at the atomic level

The "equal angles" law of refection on a flat mirror is a macroscopic phenomenon. To put it in anthropomorphic terms, how do individual photons know the orientation of the mirror so as to bounce off ...
5
votes
2answers
850 views

Principle of Reflection on atomic level

This well-observed phenomenon has, besides several others, always been a fascination to me. We are well aware of several theories, experiments, and practical applications of this well-known phenomenon,...
6
votes
1answer
559 views

Can a photon exhibit multiple frequencies?

Can a photon be a superposition of multiple frequency states? Kind of similar to how an electron can be a superposition of multiple spin states.
16
votes
3answers
5k views

How does light know which path is fastest?

We know from Fermat's principle of least time that light follows the fastest path. But how does light know which path is the fastest?
0
votes
1answer
235 views

Dichroism in uniaxial crystals

I need a same help with it. Some books where i can find a real math explanation of this effect will be good help!! simple exp of this effect will be good too)
2
votes
1answer
249 views

Optical waveguide that can displace a 4D light field

Has anyone invented an optical waveguide that can "pipe" a scene from one place to another unaltered? More precisely, I want to displace (and/or rotate) a 4D light field. An optical waveguide is an ...
11
votes
1answer
645 views

How does dynamic casimir effect generate correlated photons?

There is a recent paper on arxiv receiving lot of acclaim http://arxiv.org/abs/1105.4714 The authors experimentally show that moving a mirror of a cavity at high speeds produces light from high ...
10
votes
1answer
1k views

How are classical optics phenomena explained in QED (color)?

How is the following classical optics phenomenon explained in quantum electrodynamics? Color According to Schroedinger's model of the atom, only particular colors are emitted depending on the type ...
42
votes
3answers
8k views

How are classical optics phenomena explained in QED (Snell's law)?

How is the following classical optics phenomenon explained in quantum electrodynamics? Reflection and Refraction Are they simply due to photons being absorbed and re-emitted? How do we get to Snell'...