Questions tagged [photonics]
Photonics is the science of creating, moving, and detecting photons
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Why does non-linearity come into picture only at a large intensity of optical fields?
I have read that for sufficiently large intensities of optical fields (of the order of $10^8$), we can actually observe a non-linear relationship between the polarization and the field, given as
$$\...
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Dependence of ligh-matter strong coupling on incident laser power?
is the light matter strong coupling dependent upon incident laser power? According to the following expression the strength of the vacuum Rabi splitting can be given as
$$\hbar\Omega_\mathrm{R}=2\hbar ...
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What will be the power if I add two laser with different wavelength at same power?
I am trying to combine two lasers at 960nm and 1310nm wavelengths respectively with same power 150mW by using four wave mixing. I am planning to use a 3dB coupler for adding. I just want to know will ...
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How to achieve uniform gaussian profile? Beam profile has grainy/multimode pattern, EO says it's due to different emissivity of each phosphor atom
I'm required to make a jig that measures the divergence angle of a collimated beam.
The setup is straightforward as shown below.
The single-mode fiber optic cable, collimator & NIR camera are the ...
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Distribution function for squeezed light as a function of energy
For bosons in a thermal state, I know that the Bose-Einstein function reads
$$n(\epsilon_n)=\frac{1}{e^{\beta \epsilon_n}-1}$$
where $\epsilon_n$ is the energy and $\beta$ is the inverse temperature. ...
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Iridescent duck and photonics in nature. Why duck's head is only green?
We all know and adore pure beauty of mallard male:
I know that such iridescent colours are usually a result of feathers forming a photonic crystal with layers of air sandwiched between layers of ...
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Temporal vs Spatial Contrast in Speckle Contrast Imaging
I have been reading about Speckle Contrast Imaging recently. Its quite an interesting topic given that it should be possible with relatively inexpensive equipment. The basic premise from what I ...
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Wavelength-dependence of optical elements in integrated photonic circuits
I am interested in integrated photonic circuits or silicon photonic circuits. In the long run, I would like to analyze these circuits using a rigorous and analytical mathematical approach, taking the ...
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Can laser diode characteristics comparison be based on laser of one length?
As we know, e.g. from this website, to know the laser Transparency Threshold Current and Internal Quantum Efficiency, we need the LI curves from lasers of various widths.
However sometimes it is ...
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Refractive Index Ellipsoid for Circular Birefringence Materials
When light travels through an anisotropic medium, its refraction may depend on both its polarization and propagation. Such materials may be classified in terms of their (Linear) Birefringence as ...
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How is the physical angle between two complex electromagnetic fields defined?
If I have two electromagnetic field vectors, which are in general complex, how do I sensibly define an angle between these two fields?
Some books refer to the angle between electromagnetic fields, ...
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Calculate the effective refractive index from group index
I'm currently trying to calculate the effective refractive index $n_{eff}$ of waveguides using the (measured) group index $n_g$ and the wavelength $\lambda$.
I started with the relation between $n_{...
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Uncertainty principle and Fock states
While studying about single photon sources, I came across the following sentence on the related Wikipedia page
The Heisenberg uncertainty principle dictates that a state with an exact number of ...
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How does changing path length to align phase of two pairs of down-converted photons automatically create a GHZ quantum state between pairs?
The problem
At least one StackExchange physicist suggests "In an ideal laser, there is no entanglement whatsoever between successive emerging photons. This occurs because a laser state is ...
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Why light radiates out of the bend in dielectric waveguides?
Why EM wave radiates out of the waveguide. Is this similar to centrifugal force?
