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bio website daniel.farrell.name
location Tokyo, Japan
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visits member for 4 years, 3 months
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2d
comment How does a photon drive out the electrons in a solar cell?
This is complicated. You will have to understand band structure of semiconductors, and then semiconductor device physics to get a full answer. However, you can also describe the operation of a solar cell purely with thermodynamic, but as you are asking about the actual mechanics I don't think this is what you want. I would suggest reading Jenny Nelson's of Peter Würfel's solar cell books. It's too much to cover in a single answer.
Apr
14
comment Relation between Refractive Index and Reflection
Short answer: it goes up inn'it.
Apr
13
comment By what maximum amount can we concentrate sunlight?
The factor of two is cancelled when performing the angular integrations.
Apr
13
comment By what maximum amount can we concentrate sunlight?
This is correct and gives the general maximum solar concentration limit. Write an alternative answer that backs up your point if you have something to contribute.
Apr
12
comment Increasing the efficiency of solar cell systems
Easy to explain but open a new question because it will involve another diagram and I don't want to clutter this answer.
Apr
12
comment Increasing the efficiency of solar cell systems
This is not a duplicate of the "why do solar panels have mirrors". This question is asking about hybrid photovoltaic-thermal energy conversion which has some very interesting thermodynamic properties. Vote to keep open.
Apr
11
comment Reverse Recovery Current of a diode
What do you mean "stocked"?
Apr
7
comment Kirchoff's voltage law doesn't seem to hold in an experiment conducted with series resistor, diode and signal generator
We need to see your data to make sense of this. One comment what diode did you use. If you used a light sensitive diode (photodiode or even an LED) it is possible that background light can enter this providing a DC offset.
Apr
1
comment 3D device simulation of diode (static)
Have you checked nanohub.org? They have various web interfaces to highly professional semiconductor solvers. For teaching why not use a 1D model?
Mar
24
comment Light absorption according to “Beer-Lambert” law
Ok I guessed correctly. You want absorption coefficient as discussed in the answer above. You can also talk about an optical density too.
Mar
20
comment Aether/Ether in Electrodynamics?
Light is an excitation in a quantum field, the field permeates all space. Although not directly analogous to the aether concept this gives you the concept of the medium/field that is doing the waving.
Mar
20
comment Fresnel coefficient
Sorry, I can't help until I can read the paper of the question is updated.
Mar
20
comment Fresnel coefficient
You need to add more context to this question. For example I didn't even understand why it would be a function of angle because the refractive index doesn't change with angle (see my above point about isotropic and homogeneous materials).
Mar
20
comment Fresnel coefficient
Pay wall. Maybe you can summarise by adding a bit more context.
Mar
20
comment Kmax problem of photo electric effect
Please define the terms, and state your own thoughts. If this is homework tag as such.
Mar
20
comment Fresnel coefficient
Are you looking at isotopic and homogeneous materials? In this cast $\Delta_{ij}$ is not a function of angle. Can you link to the actual paper, this would help.
Mar
19
comment Relation between carrier temperature and lattice temperature, under injections
Hi @YueLin, that's a good question. On this site it works best when additional questions are not asked in the comments box. Mark this on as accept and up vote if useful. Then ask a new question.
Feb
23
comment Power generator powered exclusively by gravity is possible?
People should not be down voting this question. It's absolutely fine to ask this.
Feb
23
comment Question about electron-hole pair generation in depletion layer for a p-n junction photodiode
Great question but extremely broad. The PN junction is a surprisingly difficult device to understand. I would suggest breaking this down into smaller very clear questions. E.g. current flow in on junctions, why doping adds carriers to the bands, etc.
Feb
19
comment Resistance of depletion region
You might also like the hand-waving (my) answer here, physics.stackexchange.com/a/53302/1194