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Difference between thin film interference and Bragg diffraction of electron

Promoted from a comment: Because the index of refraction at x-ray wavelengths for most materials is awfully close to 1.0, while the index of refraction in the visible can easily be 1.5 and above (1....
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Is refraction a special case of diffraction according to the book by Charles Kittel?

Diffraction is caused by the confinement of the lateral extent of a wave, and it is relevant, if light is confined to a sizes comparable to its wavelength. The term diffraction has been defined by ...
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Applying Fermat's principle in Fraunhofer's diffraction

If measured from the source you take the constant phase surfaces of the propagating wave, these are the wavefronts, then Fermat's principle holds between any to points that lie on the same orthogonal ...
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Why are diffraction spikes from bright light sources longer with larger pupil than with smaller?

The radial diffraction spikes seen by normal human eyes around bright point sources are called ciliary corona. They can be seen when the apparent diameter of the point source is less than 20' (so the ...
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What is the upper limit of size for diffracting an object?

As far as I know the largest object that has been successfully diffracted is a oligoporphyrin molecule with a molecular weight of about $25000$. This was done on 2019 and is reported in Quantum ...
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Why are diffraction spikes from bright light sources longer with larger pupil than with smaller?

Its probably the effect of switching from low intensity gray receptors to normal colour receptors, that don't register the spikes. With an open iris and higher overall intensity inside the eye by ...
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What is the upper limit of size for diffracting an object?

Electrons are a relatively light particle, and therefore have a relatively long De Broglie wavelength. Electrons have been diffracted through the spaces between atoms in a crystal. A proton is about $...
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Diffraction proof

Two nothings is nothing. Reliably. So if you can pair each little virtual source with another that causes destructive interference you can be confident that when you add up the contribution from all ...
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Diffraction proof

The condition for interferences: two waves constructively interfere if their optical path differ by a multiple of the wavelength, is necessary but not sufficient. A light source emits wave trains that ...
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Diffraction proof

This is a good and practical question. When you measure the intensity of a sinusoid or something modulated by a sinusoid you are measuring $\sin^2x=\tfrac{1}{2}-\tfrac{1}{2}\cos2x$ which has a broad ...
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Diffraction proof

Welcome to SE. Lets say you have field $\mathbf{E}^{(i)}\left(\mathbf{r}\right)$ from i-th slit on the screen at position $r$. The total field at that position, due to all slits, is then: $$ \mathbf{E}...
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In the diffraction of EM waves, what kind of objects do the obstacles need to be?

Diffraction can originate from any locus at which sections of a wavefront encounter media presenting a difference in transmittance, reflectance, or refractive index (transmission velocity). Opacity is ...
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Fraunhofer Diffraction - Multiple Square Apertures

This is what I got in python (I used a 7x7 grid but it should be very similar).
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