7,490 reputation
1333
bio website sjbyrnes.com
location Massachusetts
age
visits member for 3 years, 6 months
seen 16 hours ago

Dec
14
answered Spectral properties in Solid state physics
Dec
10
comment Is there a relation between (non-) existence of magnetic monopoles and thermodynamics?
I don't understand what point you're trying to make. Are you trying to prove "If there are magnetic monopoles, nothing is thermodynamically reversible?" Or "If there are magnetic monopoles, then everything is thermodynamically reversible?" Or "If there are magnetic monopoles, the second law of thermodynamics is false"? Or what?
Dec
10
answered Is there a relation between (non-) existence of magnetic monopoles and thermodynamics?
Dec
9
awarded  Guru
Dec
9
accepted Why does a thermoelectric generator need both p and n elements?
Dec
8
answered What is the right order of creation operators?
Dec
8
answered Stimulated emission direction
Dec
8
answered Faraday's paradox
Dec
7
revised Consequences of the new theorem in QM?
added 130 characters in body
Dec
7
comment What limits the doping concentration in a semiconductor?
Well, you can write it in terms of "enthalpy of mixing" etc. But if you tell me two atoms, I cannot tell you the solubility limit (or the enthalpy of mixing or anything else useful) except by experiment or numerical simulation.
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