Can we easily extract effective masses from Si band structure?

Ravian
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can we estimate effective masses of electron and hole from the band structure if yes how? can somebody explain with reference to Si band structure?
 
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dear ravian,

yes, you can extract the effective mass from your bandstructure.
I you have a bandstructure E(k) you can extract energy distribution curves (take the program IGOR for instance) for the momentum range of interest, e.g. E(k1),E(k2) and so on.
These photoemission peaks you can then fit with a voigt function. From this fit you can
extract the peak maxima and plot them versus the crystal momentum. In a last step you can fit these data points assuming a dispersion E = hbar^2*k^2/(2m*)
 
Ravian said:
can we estimate effective masses of electron and hole from the band structure if yes how? can somebody explain with reference to Si band structure?

fk08 said:
dear ravian,

yes, you can extract the effective mass from your bandstructure.
I you have a bandstructure E(k) you can extract energy distribution curves (take the program IGOR for instance) for the momentum range of interest, e.g. E(k1),E(k2) and so on.
These photoemission peaks you can then fit with a voigt function. From this fit you can
extract the peak maxima and plot them versus the crystal momentum. In a last step you can fit these data points assuming a dispersion E = hbar^2*k^2/(2m*)

Oh no! It doesn't have to be THAT difficult.

Once you have the band structure, if you are using the semiclassical model (which you can get away with if you are dealing with Si), then the effective mass corresponds to the second derivative of the band structure, i.e.

m^* = \hbar^2 \frac{d^2E}{dk^2}^{-1}

where E is your band structure dispersion.

Zz.
 
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