Author Topic: Three Terminal device  (Read 5001 times)

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Offline jerry

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Three Terminal device
« on: September 16, 2011, 03:21 »
Dear,
    I want to figure out that when a gate electrode is introduced to a three terminal device with positive gate bias, is the energy spectrum elevated or decreased relative to zero gate bias? Thanks very much! The version i use is 11.8 alpha. The boundary condition of poisson solver is Neumann. By the way, i found that the energy spectrum (MPSH for the molecule) of the three terminal device is very different from that of two terminal device without a gate electrode (molecular junction device). For instance, when a gate bias -1V is applied, the MPSH energy spectrum of a molecule is very weird, its lowest orbital can be -700eV. Is this reasonable?
« Last Edit: September 16, 2011, 04:53 by jerry »

Offline kstokbro

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Re: Three Terminal device
« Reply #1 on: September 16, 2011, 23:53 »
This could be a bug with the new multigrid solver in 11.8. Can you post your script?

Offline jerry

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Re: Three Terminal device
« Reply #2 on: September 20, 2011, 07:50 »
Thank you for your reply. By the way, if a negative gate bias is applied, is the energy spectrum of the molecule elevated or declined?

Offline zh

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Re: Three Terminal device
« Reply #3 on: September 21, 2011, 17:09 »
When a negative gate voltage is applied, the energy spectrum of the molecule in the scattering region will be shifted down.

Please refer to here for more discussions on the gate voltage: http://quantumwise.com/forum/index.php?topic=1030.0

Offline nori

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Re: Three Terminal device
« Reply #4 on: September 21, 2011, 17:32 »
I think  the energy spectrum of the molecule under a negative gate voltage is elevated because an electron has a negative charge.