QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: coollailai on April 6, 2012, 09:59

Title: How to adding electric field in nanoribbons
Post by: coollailai on April 6, 2012, 09:59

Hi
First, in ATK, There is a Boxregion object which can creat electric field in the nanospace. If I want to add an electric field on the nanoribbon model, I just need to write those language? And where are those words placed in the whole text?
 'metallic_region1 = BoxRegion(
        1*Volt,
        xmin = 0*Angstrom, xmax = 41.439*Angstrom,
        ymin = 0*Angstrom, ymax = 0.5*Angstrom,
        zmin = 5*Angstrom, zmax = 15.*Angstrom
        )

metallic_region2 = metallic_region1(
        value = -1*Volt,
        ymin = 10*Angstrom, ymax = 12*Angstrom
        )
'

Second, is there a method to add electric field whose direction is equal to the axis of nanoribbons? Axis of nanoribbons is usually the Z-axis in the model.

I hope you can give me some helps~~~ :)

Title: Re: How to adding electric field in nanoribbons
Post by: zh on April 8, 2012, 06:14

The "Boxregion" mentioned by you is available for the gate bias voltage, not for an external electric field.  

Title: Re: How to adding electric field in nanoribbons
Post by: Nordland on April 8, 2012, 09:01

If you have more than one metallic box region with different gate biases, you will create a electric field between the two gates.
If you are not experience with programming I can recommend using the builder to add these metallic regions.

Title: Re: How to adding electric field in nanoribbons
Post by: coollailai on April 9, 2012, 04:53

Quote from: zh on April  8, 2012, 06:14

The "Boxregion" mentioned by you is available for the gate bias voltage, not for an external electric field.  

Is there a method to adding external electric field?

Title: Re: How to adding electric field in nanoribbons
Post by: zh on April 9, 2012, 08:00

It seems that the current version of ATK does not support the the functionality of applying external electric field. You may try other softwares such as abinit and quantum-espresso.

Title: Re: How to adding electric field in nanoribbons
Post by: Nordland on April 9, 2012, 14:18

It is possible to get the exact same effect as external electric field. You just have to setup it using metallic regions.

Here I have attached a system of graphene ribbon with a two metallic regions which will give an electric field strength of 0.1 V/Å.

Title: Re: How to adding electric field in nanoribbons
Post by: coollailai on April 17, 2012, 05:25

Quote from: Nordland on April  9, 2012, 14:18

It is possible to get the exact same effect as external electric field. You just have to setup it using metallic regions.

Here I have attached a system of graphene ribbon with a two metallic regions which will give an electric field strength of 0.1 V/Å.

I tried your advice and it works! thx~ :)