Author Topic: Electrochemical potential and the deformation of the device under finite bias  (Read 3514 times)

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Offline Crystal2016

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Dear sir,
How is the spatial profile of the electrochemical potential along the device treated for the transport calculations? In ATK, which function can be calculated to display it?
Another question, in ATK, has the deformation of the device under finite bias been considered? How can I calculate it and display the deformation? Does this deformation have an important impact on electronic transport? 

Offline Petr Khomyakov

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Please take a look at this tutorial, https://docs.quantumwise.com/v2017/tutorials/atk_transport_calculations/atk_transport_calculations.html. I guess Hartree Difference Potential = -|e| Electrostatic Difference Potential, where e is the elemental charge , see also https://docs.quantumwise.com/v2016/casestudies/ag_si_interface/ag_si_interface.html.

Regarding "device deformation", by default we do not optimize the device structure upon bias application. For a given bias voltage, you may calculate forces acting on atoms in the device, and investigate how the forces depend on the applied bias.

Indeed, you may do full ion relaxation at a given bias to account for the effect of current-induced forces on the device structure in the central region of the device. This is possible in QuantumATK, but this is also a very computationally-expensive calculation.

Offline Crystal2016

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