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bio website sjbyrnes.com
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Dec
7
answered What limits the doping concentration in a semiconductor?
Dec
4
comment Stimulated emission direction
You should look up optical amplifier - scholarpedia.org/article/Optical_amplification en.wikipedia.org/wiki/Optical_amplifier and more specifically gain guiding rp-photonics.com/gain_guiding.html
Dec
4
comment Why does a thermoelectric generator need both p and n elements?
I don't see any reason that ohmic losses are an inevitibly large problem in the design I drew, if you make reasonable choices about geometry etc. I agree that a large voltage is more practically useful in the final output, but it's not a big deal, you can always put a step-up voltage converter at the device output.
Dec
4
comment Why does a thermoelectric generator need both p and n elements?
Copper has 400X larger thermal conductivity than BiTe. So if you compare the heat conductance of a 1-meter-long, 1mm-diameter copper wire with the heat conductance of a 10cm^2, 1mm-thick BiTe, the BiTe will conduct more heat than the copper wire ... by a factor of 2000.
Dec
4
comment Why does a thermoelectric generator need both p and n elements?
You say "heat will be conducted away from the hot junction by the wire itself, so no electricity will flow." (I assume you mean "electrical current" not "electricity".) I don't understand how you reach that conclusion. Some heat will surely flow through the wire, but not all of it, indeed probably almost none of it. A long thin copper wire has a very low thermal conductance. In the design I drew, it is entirely possible to have 99% of the heat flow through the thermoelectric material and 1% flow through the wire. Then why should heat flow through the wire make any difference at all?
Dec
3
asked Why does a thermoelectric generator need both p and n elements?
Dec
2
answered Periodic momentum space in band structure
Nov
24
awarded  Nice Answer
Nov
10
revised Definition of mean free time in the Drude model
reference the "inspection paradox"
Nov
10
comment How to convert RGB values to physical radiometry and/or photometry quantities and back?
A few nitpicks... All modern displays and printers use sRGB, which is gamma-corrected. So you're correct that it's not logarithmic. But it's not linear either. Also, plenty of hardware can provide more accurate colors than 255-255-255, even though not all programs take advantage. See en.wikipedia.org/wiki/Color_depth
Oct
28
revised Johnson-Nyquist noise for resistive element with temperature gradient
added 834 characters in body
Oct
28
answered Johnson-Nyquist noise for resistive element with temperature gradient
Oct
22
comment How to distinguish between the spectrum of an atom in motion and the one of a scaled atom?
OP's description isn't correct, and this is a good proof. Upvoted! However, there is something along those lines that works. If I set hbar = c = 1, I can scale all quantities with units of eV^N by a factor of 10^N. So I would increase masses and energies and frequencies by 10X, I decrease lengths and durations by 10X, etc. That would definitely be a consistent way to scale the wavelength of every spectral line. See my answer.
Oct
22
revised How to distinguish between the spectrum of an atom in motion and the one of a scaled atom?
added 517 characters in body
Oct
22
revised How to distinguish between the spectrum of an atom in motion and the one of a scaled atom?
added 20 characters in body
Oct
22
answered How to distinguish between the spectrum of an atom in motion and the one of a scaled atom?
Oct
22
comment How to distinguish between the spectrum of an atom in motion and the one of a scaled atom?
Can you be more specific? Don't forget, the question is "if we decrease all the masses, does it result in decreasing all the emitted photon frequencies by the same ratio?" So the energy levels are supposed to be proportional to the masses. When you say that the hyperfine structure is proportional to me/mp, are you sure you're talking about the absolute energy level differences, rather than some ratio of splittings?
Oct
18
revised Low-cost 532nm DPSS laser modulation
added 266 characters in body
Oct
18
answered Low-cost 532nm DPSS laser modulation
Oct
18
answered Stimulated emission in Nd:silica glass, energy levels broadening and lasers