Semiconductor Physics.....Which of the following is correct? (Probabilities)

[GURMEET singh]

Consider two energy levels: E1 ,E ev above the Fermi leve and E2, E ev below the fermi level. P1 and P2 are respectively the probabilities of E1 being occupied by an electron and E2 being empty. Then

a) P1>P2
b) P1=P2
c) P1<P2
d) P1 and P2 depends upon number of free electrons

 

[M.Rehan]

I think C option is correct because
at zero absolute temperature the electrons float in a sea (surface) called fermi so below that level is empty space and probability of emptiness of E2 is greater than E1

 

[c_mitra]

I think C option is correct because at zero absolute temperature the electrons float in a sea (surface) called fermi so below that level is empty space and probability of emptiness of E2 is greater than E1

Your are correct.

At infinite temperature, option B will be correct. Lasers, that work on the principle of population inversion, corresponds to a negative temperature. Under these conditions option A will be valid.

The option d is meaningless because as soon as you have specified the Fermi level, you have fixed the number of free electrons.