All Questions
Tagged with coherent-states coherence
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What defines "minimal coherence" as a condition for the emergence of stationary interference in a chaotic wave field?
Consider the following observations:
A superposition of two electromagnetic waves with different frequencies will never produce visible interference patterns. Such waveforms will produce ...
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What does "coherent evolution" of an $N$-body quantum system mean?
In classical physics we know of coherence of waves and in quantum physics we identify coherent states.
While those are clearly defined concepts/terms, in literature we regularly encouter also that a $...
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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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Are coherent states destroyed by measurements?
For a quantum harmonic oscillator in a coherent superposition, what happens if the energy is measured? Would it collapse to an energy eigenstate (a single excitation) corresponding to the result of ...
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Coherent states and classical limit
Consider the coherent state
$$ |\phi \rangle = \exp \left( \zeta \cdot \sum_\alpha \phi_{\alpha} a_{\alpha}^\dagger \right) | 0 \rangle.$$
For the case of bosons ($\zeta = +1$), the $\phi_\alpha$'s ...
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Is it possible to “force” two separate light sources to be coherent?
I have edited this question for three reasons. They are:
1. A possible duplicate of another question. (I believe the "answer" to that question is incorrect.)
2. I received two contradictory answers.
3....
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How are coherent states in the real world made?
Coherent states are quantum states that are said to act "as classically as possible". You can define coherent states for the harmonic oscillator, or more generally for any collection of harmonic ...
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Why are coherent states of harmonic oscillators called "coherent"?
Why are coherent states of the harmonic oscillator called coherent? Coherent in what sense? Why are these states so special/useful?
From Wikipedia:
In physics, two wave sources are perfectly ...
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