QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: narin on February 10, 2024, 14:46

Title: graphene nanoribbon transistor tutorial problem
Post by: narin on February 10, 2024, 14:46

Hello

i have checked the tutorial given on the following page: https://docs.quantumatk.com/tutorials/graphene_nanoribbon_device/graphene_nanoribbon_device.html#graphene-nanoribbon-device (https://docs.quantumatk.com/tutorials/graphene_nanoribbon_device/graphene_nanoribbon_device.html#graphene-nanoribbon-device)

the conductance obtained in the given example changes about 20 times for the gate voltages of 0V and -2V. however, the reference paper given here: https://doi.org/10.1021/nl070133j (https://doi.org/10.1021/nl070133j) shows that the conductance changes 2000 times for the gate voltages of 0V and -2V.

What is the source of the big difference between the results given in the reference paper and the tutorial?

thanks.

Title: Re: graphene nanoribbon transistor tutorial problem
Post by: Anders Blom on February 13, 2024, 01:02

Although the tutorial was actually inspired by this paper, the width of the ribbon is quite different. I think that is a major factor. We do use a fast Huckel model in the tutorial vs DFT in the paper, but if the band structure is similar, this should not play a significant role (not orders of magnitude).

Title: Re: graphene nanoribbon transistor tutorial problem
Post by: narin on February 13, 2024, 12:39

Thanks, I will try by changing the width and report here.