596 reputation
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bio website daniel.farrell.name
location Tokyo, Japan
age
visits member for 3 years, 3 months
seen Apr 18 at 8:51

I know how to use the grey square -- do you?


23h
comment Carrier charge density
Isn't charge density the numbers of carriers per unit volume of material? So it's independent of size. If a have a 1km box with 1 particle in every cubic meter and a 20m box with 1 particle every cubic meter, the density of particles is the same (by definition). The total number of particles depends on volume however.
Apr
17
comment Free electron gas in two dimensions
Oh yes, very good!
Apr
17
comment Free electron gas in two dimensions
I don't know if there is an intuitive reason for this...
Apr
17
comment Temperature in a Voltaic Cell
Do you mean a chemical battery?
Apr
16
revised Why isn't there a potential difference across a disconnected diode?
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Apr
16
revised Why isn't there a potential difference across a disconnected diode?
added 1347 characters in body
Apr
16
revised Why isn't there a potential difference across a disconnected diode?
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Apr
15
answered Why isn't there a potential difference across a disconnected diode?
Apr
15
comment Possible to calculate carrier lifetime with doping concentrations?
If you can get a copy of Light-Emitting Diodes by E. Fred Schubert it explains all of this.
Apr
4
comment n-p-n p-n-p and n-n-n heterostructure for LED
celos you should start exception some answer to your questions, you have accepted non so far...
Apr
4
comment PN Junction. Germanium VS Silicon
What is your question exactly? Can you make your question really clear and simple?
Mar
29
comment n-p-n p-n-p and n-n-n heterostructure for LED
There are probably other factor as well such as sheet and contact resistance, these devices operate with quite high currents so all resistances need to be very small to avoid losses, the doping will influence this. For these reason it would be best to grow on a p-substrate and have highly doping n-contacts at the surface. So this is probably why you see both ppn and nnp structures. But you're right, which ever route you take you want to target the electron escape.
Mar
29
revised n-p-n p-n-p and n-n-n heterostructure for LED
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Mar
29
comment Why does the light travel slower in denser medium?
Great explanation.
Mar
29
comment Magnetism due to relativity?
This explains the concept nicely, youtube.com/watch?v=1TKSfAkWWN0
Mar
28
comment Reducing the Tsunami impact using Nuclear bombs
I agree with with @KyleKanos but it would be fun to calculate the momentum of the tsunami wave and calculate how much momentum can be imparted in the opposite direction using an explosion. My hunch is that the wave will have massively more momentum than any man made blast. I guess you could also try an evaporate the tsunami :)
Mar
28
comment What is the reason behind band gap narrowing in semiconductors
Hmmm... band gap narrowing seems quite complicated, here is something that makes sense, iue.tuwien.ac.at/phd/palankovski/node39.html
Mar
28
answered Semi-conductors
Mar
28
revised n-p-n p-n-p and n-n-n heterostructure for LED
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Mar
28
answered n-p-n p-n-p and n-n-n heterostructure for LED