All Questions
Tagged with coherence quantum-optics
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Modelling incoherent sources
Suppose some (coherent) light propagates onto a one-dimensional barrier with two open slits, each of length $\delta$ and separated by a distance $s$ (we can assume the centroid is known and placed at $...
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Coherence, Correlation and causality in Quantum Field Theory
I've started to study in details quantum optics and I find difficulties in linking the concepts of coherence and correlation among fields, especially because I'm building right now a background on ...
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Squeezed vacuum state
From:
Loudon, Rodney. The quantum theory of light. OUP Oxford, 2000.
Consider the single-mode quadrature-squeezed vacuum state defined by
$ | \zeta \rangle = \hat{S} (\zeta) | 0 \rangle $
where the ...
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What does it imply when we say that the waves are perfectly correlated?
I am having a hard time understanding difference between correlation and coherence. I got a nice answer for coherence here- Are two waves being in phase is the same as saying that the two waves are ...
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How to scale Poissonian light?
In quantum optics, coherent light with constant frequency, phase, and amplitude shows poissonian photon number statistics:
$$P(n) = \frac{\bar{n}^{n}}{n!}e^{-\bar{n}}.$$
A well-known result for ...
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Gaining Quantum information without destroying the coherence
I've read about new optical interference among several telescopes all around the globe. It is supposed to work by combining the quantum states of a photon A arriving at once in every telescope of the ...
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Degree of first-order coherence doesn't imply always 100% visibility?
In classic books of quantum optics visibility of interference fringes (for example in Michelson interferometer) is equal to the modulus of the degree of first order coherence $g^{(1)}$, when the ...
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First-order coherence of thermal light
so I have the following question: I want to calculate the first order coherence function for the light coming from a thermal source. I should note that this is a question I have and not a HW problem.
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Quantum and non-equilibrium properties of the radiation, emitted by "thermal light sources"
Free photon gas
Let us consider different thermal light sources, such as the Sun, an incandescent lamp, or a fluorescent bulb. In elementary quantum mechanics and statistical physics one describes the ...
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Wiener-Khinchin theorem for multimode coherent light
The Wiener-Khinchin theorem says that the Fourier transform of the degree of first order coherence is equal to the power spectral density normalized (Loudon, Quantum theory of light, pag. 102):
$F(\...
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How can sub- and super-Poissonian statistics be distinguished from bunching and antibunching?
This is my first post here, so I apologize if there's something wrong.
I am studying quantum optics and I found myself in trouble with the difference between bunching/antibunching and super poissonian/...
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Coherence and $g^{(2)}$
We talk about how coherent light has a $g^{(2)}(\tau)=1$ and thermal light has $g^{(2)}(0)=2$. However, we can talk about the coherence length of a thermal source if we put it through a very narrow ...
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Why is laser light described by a coherent state?
This is a follow-up to this recent answer by Wouter to this related question from 2015, and a comment by Emilio Pisanty underneath.
I have read the papers by Mølmer, Bartlett et al., Wiseman, and ...
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Optical coherence versus quantum coherence
Optical coherence is usually defined to be the measure of statistical correlation (for example if the phase difference is constant) of a pair of waves.
Recently I came across the notion of quantum ...
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Principle of Ergodicity in Derivation of Coherence Function
I am a bit confused about the following thing:
In the derivation of the coherence function for the electric field at two times $t_1$ and $t_2$, following simplification is made:
$$\langle E^*(t_1) E(...
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