band gap of silicon nanowire

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sana
Posts: 17
Joined: Sun May 23, 2010 8:28 pm

band gap of silicon nanowire

Post by sana » Wed Apr 20, 2011 7:17 pm

dear,
i have made calculation for silicon nanowire but i am surprised that the band gap is .406eV and i have made same calculation on catstep and dmol and amazing thing is that i got the same result. Could any one tell me that is it possible? if yes then how?


with regards,
sana

Boris
Posts: 128
Joined: Tue Feb 16, 2010 10:13 am
Location: France

Re: band gap of silicon nanowire

Post by Boris » Wed Apr 20, 2011 7:22 pm

Hi

Silicon is an insulator with a band gap of 1.12 eV and the density functional theory in its standard formulation is known to underestimate the value of the bandgap. If you want a good value for the band gap, you have to correct the density of states by using the GW approach for instance.

Boris
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Boris Dorado
Atomic Energy Commission
France
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sana
Posts: 17
Joined: Sun May 23, 2010 8:28 pm

Re: band gap of silicon nanowire

Post by sana » Wed Apr 20, 2011 7:23 pm

dear,
in Catstep and dmol i have made calculation by usin GW approx mathod

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