Questions tagged [photonics]
Photonics is the science of creating, moving, and detecting photons
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What happens to the non-axial photons of a laser cavity?
When a laser cavity is pumped, the axial photons are reflected back and forth by the cavity mirrors and so contribute to stimulated emission, but the non-axial photons do not have this opportunity. ...
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Scattering vs Stimulated Emission
I am currently reading Practical Flow Cytometry, fourth edition, by Howard M. Shapiro. The author says the following when discussing scattering:
Scattering, which explains both reflection and ...
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Why does Near Infrared (NIR) light allow deeper imaging in biological tissue in Multiphoton Microscopy?
I have been reading this paper on multiphoton microscopy (https://www.nature.com/articles/nphoton.an.2010.2) and I am very confused about something. Here is a quote from the paper:
"The NIR ...
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Frequency Chirp, Instantaneous Frequency and Photons
I understand ideas coming from Optics, such as the concept of frequency chirp and instantaneous frequency, and their use in nonlinear optics. However, I am struggling in giving them an intuitive ...
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Can photons only exist in the state of motion in a medium?
Photons are known to travel at a speed of $\rm 299 \ 792 \ 458 \ m / s$ in vacuum. Photons can be absorbed, or absorbed and re-emitted by matter. They slow down to $\rm 225,000,000 \ m/s$ in water ...
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How is the fiber alignment done in pluggable optical transceiver module (e.g., QSFP-DD)?
I recently started learning silicon photonics. After reading a few books, I understand that a single-mode fiber (especially non-polarization-maintaining fiber) supports two degenerate guided modes. ...
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Holograms and Entanglement: Does recording an entangled signal in a hologram “observe” the entangled state?
Suppose I have two photons $A$ and $B$, which are entangled.
As I have had it explained to me, entanglement works more or less as follows:
I observe or measure $A$, and find $A=S_a$, where $S_a$ ...
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