Questions tagged [laser]
Light Amplification by Stimulated Emission of Radiation. A means of creating coherent light by either driving an atomic or molecular transition in an optical cavity or firing a beam of electrons through an undulator.
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Why does LIGO use an IR laser?
The phase difference at the beam splitter of a LIGO-like interferometer is given by
$$ \Delta \phi \simeq \frac{4\pi}{\lambda} h L\ , $$
where $h$ is the gravitational wave strain (assuming a ...
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Lock-in Amplifier for Ring Resonator Characterization
Key questions:
At resonance, should I expect the LIA signal to rise to several orders of magnitude when compared to the "noise" ground?
Is it valid to reference to a "base" ...
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Michelson interferometer circular fringe pattern
By curiosity (for the fun) I'm studying the theoretical aspect of the Michelson interferometer.
I have downloaded a dozens of textbooks on Optics, read approximately fifty websites on the topic, ...
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What power of laser would be required to keep the highest $Q$-factor pendulum in detectable motion through gravitational attraction?
I believe no laboratory experiment has ever directly observed the gravitational field generated by free photons causing measurable motion in another object.
Suppose the world's highest $Q$-factor ...
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In what sense is a (laser) Gaussian pulse with spatial Gaussian profile "physical"?
1. Preliminary: Gaussian beam
There exists the "Gaussian beam" with a spatially Gaussian profile transverse to the direction of propagation; it is an approximate solution to the wave ...
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Understanding interference of non-overlapping pulses [duplicate]
I'm going to show that two delayed pulses can interfere spectrally, and that this interference is measurable, without the two pulses significantly overlapping with each other in time (or space). My ...
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Power of 2 constructive lasers originating from the same point [duplicate]
I am currently in an introductory Quantum Mechanics course. We are currently focusing on non-quantum wave interactions. We are given a problem about 2 lasers with powers of $1\, \text{kW}/\text{m}^2$ ...
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Reflectogram deconvolution via bilinear forms
I work with highly coherent laser light 1550 nm source traveling through singlemode fiber. EOM creates laser pulses ~100 ns length corresponding to $m\approx 10$ m length of pulse. I can tune laser ...
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Join Density of States Multiplying Probabilities
In the derivation of the radiative recombination rate in a direct bandgap semiconductor, my optoelectronics textbook first introduces what it calls the joint density of states (also referred to as the ...
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Can this classical electrodynamic approach generate entangled photons?
The interaction of light with a crystal, when generating a new color involves the impending light resonate the electrons of the constituent atoms. If this description is correct, could we generate ...
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Why do we need to use laser pulses for Atom probe tomography of insulators and semiconductors?
From the research I have done the larger penetration of externally applied $E$-fields into insulators and semiconductors (due to less internal shielding) worsens the spatial resolution since a ...
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Meniscus lens vs. concave for changing focus
I am working on a laser setup where I have been recently asked to change the position of the focus by adding a negative Meniscus lens at a certain point in front of the focus. This should move the ...
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Does the energy of lights change when two lights combine? [closed]
This question comes from a imagination of mine. If there are 2 laser light sources that are totally the same, which means the amplitude, wavelength, and phase of the two lights are equal. Let’s assume ...
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What is the correct phase of reflected and incident light in an optical cavity, and why is the reflected light vanish on resonance?
I've run into a bit of confusion about the intensity of reflected light exiting from an optical cavity. In three separate sources (mainly in the context of PDH locking), I've seen that the total ...
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Twisting a laser with the Quantum Zeno Effect
I thought of an experiment in QM with a predicted result that seems kind of absurd to me, so I want to know what I am missing in my mental model. I tried to perform the experiment using a consumer-...
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