Dear Dr.Engelund
Very much thanks from your answers. You have said " if you are using a doped
electrode, then you have moved the
Fermi level out of the band gap", but this is not seen in band structure
calculation and Fermi level is setting between band gap.Exactly this is my
problem.
excuse me for repeating questions.
best regards
Zihab Sohbatzadeh,
PhD Student,
Dept. of Physics,
Faculty of Science,
Ferdowsi University of Mashhad ,
Mashhad ,
Iran .
Mobile: +98 9153490795
Phone: +98 511 8818534
Fax : +98 511 8796416
________________________________
From: Mads Engelund <[email protected]>
To: [email protected]
Sent: Thursday, May 29, 2014 12:10 PM
Subject: Re: [SIESTA-L] semiconductot electrod
Ok, if you are using a doped electrode, then you have moved the Fermi level out
of the band gap, so that is good, and in principle it should work.
But you should expect to need a lot more layers in the central
region than for a metal. It depends on the screening length of the
semiconductor you are using and the properties you are
investigating. You need to do a very careful convergence study with
the size of the central region, especially if you expect the central
region to be charged.
Mads Engelund
On 05/29/2014 09:11 AM, zehab sohbatzadeh wrote:
Very thanks from your reply Dr.Engelund.
>Clearly I dont understand that one can use semiconductor electrode or no? I
>use Fe-doped 6AGNR as electrode but it has gap when I relax it alone and then
>calculate its band gap.
>thank you in advance
>
>
>Zihab Sohbatzadeh,
>PhD Student,
>Dept. of Physics,
>Faculty of Science,
>Ferdowsi University of Mashhad ,
>Mashhad ,
>Iran .
>Mobile: +98 9153490795
>Phone: +98 511 8818534
>Fax : +98 511 8796416
>
>
>________________________________
> From: Mads Engelund <[email protected]>
>To: [email protected]
>Sent: Thursday, May 29, 2014 10:56 AM
>Subject: Re: [SIESTA-L] semiconductot electrod
>
>
>
>Short answer, probably not.
>
>The chemical potential is assumed to be constant once
you reach the electrodes - not really consistent with
the band bending of semiconductors.
>
>If you can use some tricks to move the fermi level out
of the gap and use a very large central region(only
doable for interface studies) then...maybe. But be
very careful with checking convergence with size.
>
>Mads Engelund
>
>
>On 05/29/2014 06:54 AM, zehab sohbatzadeh wrote:
>
>Hi dear users
>>Can we use semiconductor electrodes in transport calculation?
>>best regards
>>
>>
>>Zihab Sohbatzadeh,
>>PhD Student,
>>Dept. of Physics,
>>Faculty of Science,
>>Ferdowsi University of Mashhad ,
>>Mashhad ,
>>Iran .
>>Mobile: +98 9153490795
>>Phone: +98 511 8818534
>>Fax : +98 511 8796416
>
>
>
