Re: [SIESTA-L] Transmission spectrum varies greatly with TBT.Contours.Eta
Hi Nick, Noted, and thank you for your reply! best regards Sukhito Teh National Tsing Hua University On Sat, Mar 5, 2022 at 5:01 AM Nick Papior wrote: > Hi, > > No, I would say you need to conduct more experiments in trying to > understand your system's sensitivity and convergences a bit better. > > Den tor. 3. mar. 2022 kl. 22.02 skrev Sukhito Teh : > >> Thank you Nick, I benefited a lot for going through the tutorials that >> you provided. >> Since the transmission varies greatly with eta, can I say that the >> absolute value of the transmission function (and thus the current >> calculated) is not really meaningful? >> >> Best regards, >> Sukhito Teh >> University of National Tsing Hua University >> >> On Sat, Feb 26, 2022 at 5:02 AM Nick Papior wrote: >> >>> There isn't per see a problem with the calculations. When the >>> transmission is low, increasing the ETA value will generally smear out the >>> transmissions, lowering the overall T. Please do understand what the Eta >>> value does and what it means in the physical picture. >>> >>> Instead of looking at the transmission, I would look at the DOS on >>> certain sites and check how they evolve with eta values, also take into >>> account the energy spacing in your integration window. For example please >>> carefully understand slide 6 in this presentation: >>> https://github.com/zerothi/ts-tbt-sisl-tutorial/releases/download/v2021.05/Slide_Monday_0900.pdf >>> The discussion about energies and eta values is very important in what >>> you are experiencing. >>> >>> Den tor. 24. feb. 2022 kl. 22.03 skrev Sukhito Teh >> >: >>> Dear developers and users, I am trying to calculate the spin polarized current flowing through magnetic junction MoS2/graphene/MoS2 with Co as electrodes ( https://journals.aps.org/prb/abstract/10.1103/PhysRevB.103.165407). For the spin up current (parallel to both Co electrode's spins), the transmission function seems to retain its feature with increasing value of TBT.Contours.Eta, but the transmission function for spin down current varies greatly with it. Does this imply my calculation with transiesta is actually problematic? Or is it normal to use an Eta as large as 100 meV in order to get converged results for tbtrans calculation? I had attached the figures for transmission functions, and also input files for the calculation. Thank you for your attention. Link to Figures of Transmission Spectrum https://ibb.co/kQ4kL70 https://ibb.co/8P7JtbD https://ibb.co/VVVkf8z Best regards, Sukhito Teh University of National Tsing Hua University -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) >>> >>> >>> -- >>> Kind regards Nick >>> >>> -- >>> SIESTA is supported by the Spanish Research Agency (AEI) and by the >>> European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) >>> >> >> -- >> SIESTA is supported by the Spanish Research Agency (AEI) and by the >> European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) >> > > > -- > Kind regards Nick > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) > -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
Re: [SIESTA-L] Transmission spectrum varies greatly with TBT.Contours.Eta
Hi, No, I would say you need to conduct more experiments in trying to understand your system's sensitivity and convergences a bit better. Den tor. 3. mar. 2022 kl. 22.02 skrev Sukhito Teh : > Thank you Nick, I benefited a lot for going through the tutorials that you > provided. > Since the transmission varies greatly with eta, can I say that the > absolute value of the transmission function (and thus the current > calculated) is not really meaningful? > > Best regards, > Sukhito Teh > University of National Tsing Hua University > > On Sat, Feb 26, 2022 at 5:02 AM Nick Papior wrote: > >> There isn't per see a problem with the calculations. When the >> transmission is low, increasing the ETA value will generally smear out the >> transmissions, lowering the overall T. Please do understand what the Eta >> value does and what it means in the physical picture. >> >> Instead of looking at the transmission, I would look at the DOS on >> certain sites and check how they evolve with eta values, also take into >> account the energy spacing in your integration window. For example please >> carefully understand slide 6 in this presentation: >> https://github.com/zerothi/ts-tbt-sisl-tutorial/releases/download/v2021.05/Slide_Monday_0900.pdf >> The discussion about energies and eta values is very important in what >> you are experiencing. >> >> Den tor. 24. feb. 2022 kl. 22.03 skrev Sukhito Teh > >: >> >>> Dear developers and users, >>> I am trying to calculate the spin polarized current flowing >>> through magnetic junction MoS2/graphene/MoS2 with Co as electrodes ( >>> https://journals.aps.org/prb/abstract/10.1103/PhysRevB.103.165407). For >>> the spin up current (parallel to both Co electrode's spins), the >>> transmission function seems to retain its feature with increasing value of >>> TBT.Contours.Eta, but the transmission function for spin down current >>> varies greatly with it. >>> Does this imply my calculation with transiesta is actually problematic? >>> Or is it normal to use an Eta as large as 100 meV in order to get converged >>> results for tbtrans calculation? >>> I had attached the figures for transmission functions, and also input >>> files for the calculation. >>> Thank you for your attention. >>> >>> Link to Figures of Transmission Spectrum >>> https://ibb.co/kQ4kL70 >>> https://ibb.co/8P7JtbD >>> https://ibb.co/VVVkf8z >>> >>> Best regards, >>> Sukhito Teh >>> University of National Tsing Hua University >>> >>> -- >>> SIESTA is supported by the Spanish Research Agency (AEI) and by the >>> European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) >>> >> >> >> -- >> Kind regards Nick >> >> -- >> SIESTA is supported by the Spanish Research Agency (AEI) and by the >> European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) >> > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) > -- Kind regards Nick -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
Re: [SIESTA-L] Transmission spectrum varies greatly with TBT.Contours.Eta
Thank you Nick, I benefited a lot for going through the tutorials that you provided. Since the transmission varies greatly with eta, can I say that the absolute value of the transmission function (and thus the current calculated) is not really meaningful? Best regards, Sukhito Teh University of National Tsing Hua University On Sat, Feb 26, 2022 at 5:02 AM Nick Papior wrote: > There isn't per see a problem with the calculations. When the transmission > is low, increasing the ETA value will generally smear out the > transmissions, lowering the overall T. Please do understand what the Eta > value does and what it means in the physical picture. > > Instead of looking at the transmission, I would look at the DOS on certain > sites and check how they evolve with eta values, also take into account the > energy spacing in your integration window. For example please carefully > understand slide 6 in this presentation: > https://github.com/zerothi/ts-tbt-sisl-tutorial/releases/download/v2021.05/Slide_Monday_0900.pdf > The discussion about energies and eta values is very important in what you > are experiencing. > > Den tor. 24. feb. 2022 kl. 22.03 skrev Sukhito Teh : > >> Dear developers and users, >> I am trying to calculate the spin polarized current flowing >> through magnetic junction MoS2/graphene/MoS2 with Co as electrodes ( >> https://journals.aps.org/prb/abstract/10.1103/PhysRevB.103.165407). For >> the spin up current (parallel to both Co electrode's spins), the >> transmission function seems to retain its feature with increasing value of >> TBT.Contours.Eta, but the transmission function for spin down current >> varies greatly with it. >> Does this imply my calculation with transiesta is actually problematic? >> Or is it normal to use an Eta as large as 100 meV in order to get converged >> results for tbtrans calculation? >> I had attached the figures for transmission functions, and also input >> files for the calculation. >> Thank you for your attention. >> >> Link to Figures of Transmission Spectrum >> https://ibb.co/kQ4kL70 >> https://ibb.co/8P7JtbD >> https://ibb.co/VVVkf8z >> >> Best regards, >> Sukhito Teh >> University of National Tsing Hua University >> >> -- >> SIESTA is supported by the Spanish Research Agency (AEI) and by the >> European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) >> > > > -- > Kind regards Nick > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) > -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
Re: [SIESTA-L] Transmission spectrum varies greatly with TBT.Contours.Eta
There isn't per see a problem with the calculations. When the transmission is low, increasing the ETA value will generally smear out the transmissions, lowering the overall T. Please do understand what the Eta value does and what it means in the physical picture. Instead of looking at the transmission, I would look at the DOS on certain sites and check how they evolve with eta values, also take into account the energy spacing in your integration window. For example please carefully understand slide 6 in this presentation: https://github.com/zerothi/ts-tbt-sisl-tutorial/releases/download/v2021.05/Slide_Monday_0900.pdf The discussion about energies and eta values is very important in what you are experiencing. Den tor. 24. feb. 2022 kl. 22.03 skrev Sukhito Teh : > Dear developers and users, > I am trying to calculate the spin polarized current flowing > through magnetic junction MoS2/graphene/MoS2 with Co as electrodes ( > https://journals.aps.org/prb/abstract/10.1103/PhysRevB.103.165407). For > the spin up current (parallel to both Co electrode's spins), the > transmission function seems to retain its feature with increasing value of > TBT.Contours.Eta, but the transmission function for spin down current > varies greatly with it. > Does this imply my calculation with transiesta is actually problematic? Or > is it normal to use an Eta as large as 100 meV in order to get converged > results for tbtrans calculation? > I had attached the figures for transmission functions, and also input > files for the calculation. > Thank you for your attention. > > Link to Figures of Transmission Spectrum > https://ibb.co/kQ4kL70 > https://ibb.co/8P7JtbD > https://ibb.co/VVVkf8z > > Best regards, > Sukhito Teh > University of National Tsing Hua University > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) > -- Kind regards Nick -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
