Questions tagged [interferometry]
Interferometry is the name for a class of measurement techniques based on the interference of coherent optical fields or other electromagnetic radiation. Generally, Interferometric measurements are extremely accurate, but can be difficult to perform. Common uses for interferometry are optical component metrology and stellar interferometry, although there are many applications.
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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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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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Relativistic effects in a centrifuge interferometer, theoretical versus practical
Imagine an interferometer where one arm includes a path travelling from the rotation axis to a mirror rotating around said axis and back out again. Would the interference pattern be at all dependent ...
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Fabry-Perot Interferometer, "localized fringes at infinity"
We had performed a Fabry-Perot interferometer experiment: two main objectives was to find the wavelength of a laser source and to find the difference in wavelengths of a sodium doublet lamp.
The first ...
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Micro-oscillations in laser interferometry signal
Here is my data from performing michelson interferometry:
Voltage is measured using a photodiode as a mirror is translated. I then convert this to mirror position using the mirror velocity. Mirror is ...
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Interferometry of gravitational lens images?
The finest feature a telescope can resolve is inversely proportional to its aperture.
Interferometry is used to create telescopes with large (or very large) effective aperture size (although less ...
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What is the phase of light that has been reflected from a moving mirror and arrives a detector?
I'm trying to understand how interferometry works with a moving mirror (target) in the measurement arm.
Let's say a light source in an interferometer emits light toward a moving target mirror with ...
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Is there a theoretical limit on the amplitude or frequency of gravitational waves that can be detected with certainty?
Laser interferometer systems like LIGO are used for astronomy, tracking massive collisions in space, but anything with mass that accelerates will generate gravitational waves. That makes everyday ...
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Can a symmetric vertical Michelson interferometer reveal gravitational anisotropy in light speed without being confounded by mechanical distortion?
I'm exploring whether a vertical Michelson–Morley–type experiment can detect directional anisotropy in the speed of light due to gravity, and whether a specific symmetrically mounted setup can cancel ...
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Could a vertical Michelson–Morley experiment detect gravitational anisotropy in the speed of light?
Most Michelson–Morley-type experiments have been performed with horizontal interferometer arms, and have found no detectable anisotropy in the speed of light, placing upper bounds at the level of 1 ...
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Length contraction on a train measured with an interferometer
Imagine I took an L-shaped interferometer on a train, and adjusted the arm lengths such that there was total destructive interference at the interferometer output, then placed one arm in the direction ...
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Mach-Zehnder Interferometer Question
In this interferometer, the photon is interfering with itself. The polarization angles are the same, so the resulting counts display an interference pattern described by the equation:
$$P = \frac{1}{2}...
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How can two light rays created by a gravitational lens interfere?
In "Quantum Theory and Measurement", Wheeler proposed an interference experiment performed on light rays emanating from a stellar object behind a gravitational lens to demonstrate the "...
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How can radio synthesis telescopes do interferometry from atomic hydrogen clouds(say) when the light from the cloud is incoherent?
The atoms in a hydrogen cloud are undergoing 21cm spin flips in an incoherent/asynchronous manner so the light they produce isn't coherent, is it?
If so, how can we do interferometry with multiple ...
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Normal ordering of passive linear optics
I am trying to normally-order operators in quantum optics. Having normally-ordered expressions is useful when evaluating expectation values in quantum optics, as most of the times we can write the ...
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