Hi Abbout, I have a matrix giving me the complex wave function at each site. How do I know which mode (m/n) do the amplitudes correspond to? Also, I am not aware of the method to get wavenumbers k_m. Could you kindly help me out with that as well?
Thanks for the help! On Sun, Jun 10, 2018 at 1:45 PM Abbout Adel <abbout.a...@gmail.com> wrote: > Hi Shivang, > > The transmitted wave function transmitted in the mode m (and coming from > the mode n) is: > > t_mn exp(i k_m). >> > > Since you have the transmitted amplitudes and the wavenumbers k_m, you > have everything for your request. > > > I hope this helps. > Adel > > > > On Fri, Jun 8, 2018 at 11:09 PM, Shivang Agarwal < > shivang.agar...@iitgn.ac.in> wrote: > >> Hi, >> >> I had one more query. Would it be possible to calculate and plot the >> magnitude and phase of the complex wave function of each transmission mode >> separately? >> >> Regards, >> Shivang >> >> On Thu, Jun 7, 2018 at 8:29 PM Shivang Agarwal < >> shivang.agar...@iitgn.ac.in> wrote: >> >>> Hi Abbout, >>> >>> Thanks for swift response. >>> Indeed, the kwant.wavefunction module gives me a complex number. I had >>> been working on probability (wavefunction squared) and had overlooked the >>> phase part. A noob mistake. >>> >>> Appreciate your help! >>> >>> Shivang >>> >>> On Thu, Jun 7, 2018 at 11:53 AM Abbout Adel <abbout.a...@gmail.com> >>> wrote: >>> >>>> Dear Shivang, >>>> >>>> To get the matrix Gamma you can do: >>>> >>>> sys = sys.finalized() >>>> lead_L = sys.leads[0] >>>> Sigma_L = lead_L.selfenergy(energy) >>>> Gamma_L = -2*imag(Sigma_L) >>>> >>>> You can find the details in this answer by Joseph [1]. >>>> To get directly the transmission matrix t you can do: >>>> t=kwant.smatrix(sys,energy, *out_leads=[1]*, *in_leads=[0]*).data >>>> #I suppose you have just two leads. >>>> >>>> Now, since your aim is to get the wave function, the module >>>> kwant.wavefunction gives you the wavefunction as a complex number (module >>>> and *phase*). So, your claim that you are unable to get the phase is >>>> confusing! >>>> >>>> I hope this helps. >>>> Adel >>>> >>>> [1] >>>> https://mailman-mail5.webfaction.com/pipermail/kwant-discuss/2015-May/000355.html >>>> >>>> >>>> >>>> Abbout Adel >>>> >>>> On Wed, Jun 6, 2018 at 11:53 PM, Shivang Agarwal < >>>> shivang.agar...@iitgn.ac.in> wrote: >>>> >>>>> Hello authors, >>>>> >>>>> I am trying to perform an eigenchannel analysis of a graphene >>>>> nanoribbon. For that I will be using the formula : >>>>> *T(E) = ГL(E)½ GC†(E) ГR(E) GC(E) ГL(E)½ * >>>>> where *ГL(E)* is the coupling matrix between the left lead and the >>>>> conductor, *GC(E)* is the greens function matrix of the conductor >>>>> (system) and '†' is the dagger operator. The equation is from the >>>>> following paper: >>>>> https://journals.aps.org/prb/pdf/10.1103/PhysRevB.73.075429 >>>>> >>>>> (1) Now as far as I know, Kwant allows us to calculate transmission as >>>>> a number T(E). What I need for my code is 't' where Trace(t*†*t) = >>>>> T(E). Could somebody let me know how can I get the desired quantity 't'?. >>>>> But I don't know how I can get the coupling matrix *ГL(E) between the >>>>> left (or right) lead and the conductor* >>>>> >>>>> (2) Also, we know that t = *ГL(E)½ GC(E) ГR(E)½ .But I don't know how >>>>> I can get the coupling matrix ГL(E) between the left (or right) lead and >>>>> the conductor. Is it possible to get too?* >>>>> >>>>> *PS - My aim is to find the wavefunctions inside the nanoribbon (which >>>>> Kwant can do very conveniently) and also their phases! I have found the >>>>> wavefunctions but am unable to find their phases. If there's any other way >>>>> to find it that would also be extremely helpful.* >>>>> >>>>> *Any help would be greatly appreciated.* >>>>> >>>>> *Thanks and Regards,* >>>>> *Shivang Agarwal* >>>>> -- >>>>> *Shivang Agarwal* >>>>> Junior Undergraduate >>>>> Discipline of Electrical Engineering >>>>> IIT Gandhinagar >>>>> >>>>> Contact: +91-9869321451 >>>>> >>>> >>>> >>>> >>>> -- >>>> Abbout Adel >>>> >>> >>> >>> -- >>> *Shivang Agarwal* >>> Junior Undergraduate >>> Discipline of Electrical Engineering >>> IIT Gandhinagar >>> >>> Contact: +91-9869321451 >>> >> >> >> -- >> *Shivang Agarwal* >> Junior Undergraduate >> Discipline of Electrical Engineering >> IIT Gandhinagar >> >> Contact: +91-9869321451 >> > > > > -- > Abbout Adel > -- *Shivang Agarwal* Junior Undergraduate Discipline of Electrical Engineering IIT Gandhinagar Contact: +91-9869321451
