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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18 views
laser wave functions excitation state change question
Supposing an Einstein-Bose condensate where electrons are excited to the point of coherent light emiting.
Regarding lighwave coherence:
* Does the exitation state make the coherence itself ...
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28 views
Welding physics (black body and heat conductance)?
If I have two pieces of steel that I would like to weld with a laser (say $d$ in diameter). If I wanted to melt the two pieces to a depth of $d$ along the edge and then combine them together, how much ...
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39 views
Time reversed laser
Recently, I read an article on time reversed laser. I don't know why they call it a time reversed. I have a doubt that why they use two laser in the device. And what is an anti-laser?
The device ...
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24 views
Calculating population ratio for radiative transmissions in lasers
I'm trying to understand how the ratio of population is related to the energy gap between two energy levels. If an emission of a wavelength at 550nm is given off at room temperature (293K), then what ...
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1answer
153 views
Calculating laser wavelength/power to cause emission of light in a gas?
It's been a long, long time since I've had to worry about electron excitation levels and band gaps. Please forgive (and correct!) my terminology and misconceptions. I've also posted this in the ...
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1answer
299 views
Increase of threshold current by temperature in a laser diode
I read somewhere that if we increase the temperature of the material in a laser diode the threshold current for lasing also increases. Can someone explain to me why is this happening? What is the ...
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51 views
on interference [closed]
A laser is oscillating at two frequencies v1 and v2 such that v2-v1=c/2l where resonator length. If the laser is used in an interference experiment,what is the minimum path difference between ...
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1answer
77 views
Density and statistical models for visible air dust
If a laser beam is looked at from the side versus a dark background, a sparkling effect can be seen caused by dust particles in the air hit by the beam.
Is there any simple model or coarse ...
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1answer
249 views
How does a Blu-Ray work? [closed]
I've just bought a BluRay, and I want to know how it works. I'm not searching for a high-level scientific explanation--just a simple answer.
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55 views
How much energy would a UV laser need to burn through 30cm of steel when fired from orbit? [closed]
For balancing a role playing game, I'd like to know how much energy a UV laser would need to burn through 30 cm of steel in one second. The laser is installed on a platform in orbit (say 10'000 km ...
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3answers
221 views
A Different Lasing Medium [closed]
Powerful lasers are highly intense, diverge negligibly and are also coherent. These radiations are emitted through partially reflecting mirrors after simultaneous reflections within the lasing medium. ...
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53 views
Which beam splitting ratio has uncoated glass for 420 nanometers coherent laserlight? [closed]
Which beam splitting ratio has uncoated glass for 420 nanometers coherent laserlight?
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45 views
Is there a regular glasses that I can see invisible light? [closed]
I'm researching a technology: an invisible light that can be seen by a modified standard glasses.
I can not use a pair of glass that looks like a sunglasses.
Did it exist? Any idea?
