What is the min and max power that avalanche photodiodes can receive?
Can someone please tell me the characteristic curve of an avalanche photodiode?
An avalanche diode has a pn junction in it with high doping. This leads to a thin depletion region. For a given voltage a very thin depletion region will have a high field, because field is voltage divided by distance and you've made the distance small.
A high field means that the drift velocity of the electrons flowing through the depletion region will be high. The high velocity means high kinetic energy.
An avalanche diode is simply one that has been optimized such that this kinetic energy is high enough that when electrons flow through the lattice they have enough energy to kick and release bound valence electrons.
If this kinetic energy imparted to valence electrons is sufficient, the electrons are no longer bound but become free. They also can attain a high velocity due to the field, and in turn kick off further valence electrons, which then can do the same. Because of this cascade in numbers of electrons, we call this an "avalanche."
Regarding your other questions, you are better off Googling a few data sheets and seeing yourself what is out there at present.
An avalanche diode has a pn junction in it with high doping. This leads to a thin depletion region. For a given voltage a very thin depletion region will have a high field, because field is voltage divided by distance and you've made the distance small.
A high field means that the drift velocity of the electrons flowing through the depletion region will be high. The high velocity means high kinetic energy.
An avalanche diode is simply one that has been optimized such that this kinetic energy is high enough that when electrons flow through the lattice they have enough energy to kick and release bound valence electrons.
If this kinetic energy imparted to valence electrons is sufficient, the electrons are no longer bound but become free. They also can attain a high velocity due to the field, and in turn kick off further valence electrons, which then can do the same. Because of this cascade in numbers of electrons, we call this an "avalanche."
Regarding your other questions, you are better off Googling a few data sheets and seeing yourself what is out there at present.
I will just add to the previous answer that avalanche photodiodes are normally operated at strong reverse bias in order to get as high as possible an electric field in the depletion region.
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