Mailman 3 November 2020 - Kwant-discuss

extracting scattering states momenta with Kwant
by Vardan Kaladzhyan 17 Nov '20

17 Nov '20

Dear Kwant developers, I was wondering if there were any examples of extracting the momenta of the scattering states? I have found several functions in the documentation that seem to cover what I would like to do, however, I have not managed to implement them, unfortunately. To be more specific, my problem is such that there are 'bands' in the left lead, and I would like to see how many scattering states (+their momenta) Kwant finds at a given value of the chemical potential in the lead. Thank you in advance for your help! Cheers, Vardan.

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how to plot the Charge density with multiple orbitals per site
by Xiangru Kong 13 Nov '20

13 Nov '20

Hi all, I want to plot the the Charge density using kwant.plot method, I want to know how to plot the Charge density in a system with multiple orbitals per site. Here is some pesuo codes: ..... syst = kwant.Builder() ..... model= kwant.wraparound.wraparound(syst).finalized() ham=model.hamiltonian_submatrix (eigen,evecs) = la.eigh(ham) def site_size(i): return 2 * wf[i] / wf.max() kwant.plot(model, site_size=site_size, site_color=(0, 0, 1, 0.3),fig_size=(10,10)); ********* In my codes, I just found len(model.sites)=6, that is the number of sites in the unit cell, however, due to there are multiple orbitals per site, the len(evecs[:,i])=22 orbitals. So I want to know the real infortion when using kwant.plot? Like what I just posted, it only plot evecs[:6,i]**2 functions? Thanks Xiangru

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questions for wraparound in Kwant
by dae han Park 10 Nov '20

10 Nov '20

Dear all I want to draw a contour plot of the first Brillouin zone and band structure along the path of high symmetry points by using Kwant. In Kwant, I know that "kwant.wraparound.plot_2d_bands" function shows the Brillouin zone in 3D. I read a kwant official documentary to find the information that I want, but I couldn't find the solution. My questions are as follows; 1) are there functions in kwant to draw 2D contour plot of the Brillouin zone and the band structure along the path of high symmetry points? 2) If it is not, could I extract data shown from kwant.wraparound.plot_2d_bands? Thank you for reading my email. Sincerely, Daehan Park. ===================================== Department of Physics, Soongsil University, 369, Sangdo-ro, Dongjak-gu, Seoul 156-743, Republic of Korea (South Korea) mail: m31phy(a)gmail.com ===================================== ᐧ

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