Re: [Kwant] Difference between hop[0].tag and hop[1].tag
Dear Adel, I do thank you for link. Everything is clear now since the linke describes in detains (site, family, tag, etc) Regards Adel Le mar. 10 sept. 2019 à 09:40, Abbout Adel a écrit : > Dear Adel, > > It seems that you did not get it correctly. A hopping is a tuple of two > sites which make a bond in your lattice. So the direction is not important. > > Hop=(site1,site2) > Hop[0]=site1 > Hop[1]=site2 > > I suggest to you to have a look at the frequently asked questions in kwant > [1]. It explains a lot of interesting things. > > I hope this helps. > Regards, > Adel > > [1] https://kwant-project.org/doc/1/tutorial/faq > > On Mon, Sep 9, 2019 at 2:15 PM Adel Belayadi wrote: > >> Dear Joseph. >> Thank you for your reply. If I got it well, you mean the first site the >> hopping along x direction and second site the hopping in the y direction. >> Best >> A.BELAYADI >> >> Le lun. 2 sept. 2019 à 09:15, Joseph Weston >> a écrit : >> >>> Hello, >>> >>> >>> What is the difference between hop[0].tag and hop[1].tag >>> >>> hop[0].tag is the tag of the first site in the hopping and hop[1].tag is >>> the tag of the second site in the hopping. >>> >>> >>> >>> My second question >>> the onsite fuction for example: def onsite(site, V):return V >>> >>> why it depends on site where the shape functions for example >>> def circle(pos): rsq = pos[0] ** 2 + pos[1] ** 2 >>> depends on pos >>> >>> Because when creating a shape in realspace you typically only care >>> about the position, whereas your onsite matrix elements could potentially >>> depend on other things (e.g. the lattice that the site is from) >>> >>> >>> Happy Kwanting, >>> >>> >>> Joe >>> >> > > -- > Abbout Adel >
Re: [Kwant] help conda
Hi, > Dear Sir, > I have a problem to install Kwant when download the Pre-built packages ( > Anaconda package ). That is to say I can't download the package. My > operating systems is Microsoft Windows. Can you help me. Please provide more information; what exact steps did you take when trying to install Kwant. Did you use the command line and the following command: conda install -c conda-forge kwant or did you use the Anaconda GUI to install the package? In the latter case did you make sure to enable the "conda-forge" channel? Happy Kwanting, Joe signature.asc Description: OpenPGP digital signature
Re: [Kwant] How to solve the Hamiltonian matrix with off-diagonal terms?
Hi, > We consider the values of the conservation law based on the > off-diagonal term of Hamiltonian matrix, details are as follows: > > > > H = tinyarray.array([[0, 0, 0, 1, 0, 0], > > [0, 0, 0, 0, 1, 0], > > [0, 0, 0, 0, 0, 1], > > [1, 0, 0, 0, 0, 0], > > [0, 1, 0, 0, 0, 0], > > [0, 0, 1, 0, 0, 0]]) > I don't really understand; is this the full Hamiltonian? > spin_block = tinyarray.array([[0, 0, 0, 1, 0, 0], > > [0, 0, 0, 0, 1, 0], > > [0, 0, 0, 0, 0, 1], > > [-1, 0, 0, 0, 0, 0], > > [0, -1, 0, 0, 0, 0], > > [0, 0, -1, 0, 0, 0]]) > > And we add “conservation_law= - spin_block” in “lead=kwant.Builder()” > > > > The program can not work, and prompt error: > > > > IndexError: index 2 is out of bounds for axis 0 with size 2 > There is not enough information for me to be able to help you. Please attach a complete Kwant script. Happy Kwanting, Joe signature.asc Description: OpenPGP digital signature
Re: [Kwant] How to solve the Hamiltonian matrix with off-diagonal terms?
Dear Yan, If you post a small part of your program reproducing this error message, someone may help you. Regards, Adel On Mon, Sep 9, 2019 at 12:58 PM X.F.Yan wrote: > > > Dear sir, > > > Recently, we use Kwant to solve for Hamiltonian matrix with off-diagonal > terms. We successfully calculate the energy band structure and total > conductance. But unfortunately, we tried to compute the spin conductance > without success. > > > > We consider the values of the conservation law based on the off-diagonal > term of Hamiltonian matrix, details are as follows: > > > > H = tinyarray.array([[0, 0, 0, 1, 0, 0], > > [0, 0, 0, 0, 1, 0], > > [0, 0, 0, 0, 0, 1], > > [1, 0, 0, 0, 0, 0], > > [0, 1, 0, 0, 0, 0], > > [0, 0, 1, 0, 0, 0]]) > > > > > > > > spin_block = tinyarray.array([[0, 0, 0, 1, 0, 0], > > [0, 0, 0, 0, 1, 0], > > [0, 0, 0, 0, 0, 1], > > [-1, 0, 0, 0, 0, 0], > > [0, -1, 0, 0, 0, 0], > > [0, 0, -1, 0, 0, 0]]) > > And we add “conservation_law= - spin_block” in “lead=kwant.Builder()” > > > > The program can not work, and prompt error: > > > > IndexError: index 2 is out of bounds for axis 0 with size 2 > > > > Please help me. > > > > Thank you, > > > > Kind regards, > > X.F.Yan > > > > > > > -- Abbout Adel
Re: [Kwant] Difference between hop[0].tag and hop[1].tag
Dear Adel, It seems that you did not get it correctly. A hopping is a tuple of two sites which make a bond in your lattice. So the direction is not important. Hop=(site1,site2) Hop[0]=site1 Hop[1]=site2 I suggest to you to have a look at the frequently asked questions in kwant [1]. It explains a lot of interesting things. I hope this helps. Regards, Adel [1] https://kwant-project.org/doc/1/tutorial/faq On Mon, Sep 9, 2019 at 2:15 PM Adel Belayadi wrote: > Dear Joseph. > Thank you for your reply. If I got it well, you mean the first site the > hopping along x direction and second site the hopping in the y direction. > Best > A.BELAYADI > > Le lun. 2 sept. 2019 à 09:15, Joseph Weston a > écrit : > >> Hello, >> >> >> What is the difference between hop[0].tag and hop[1].tag >> >> hop[0].tag is the tag of the first site in the hopping and hop[1].tag is >> the tag of the second site in the hopping. >> >> >> >> My second question >> the onsite fuction for example: def onsite(site, V):return V >> >> why it depends on site where the shape functions for example >> def circle(pos): rsq = pos[0] ** 2 + pos[1] ** 2 >> depends on pos >> >> Because when creating a shape in realspace you typically only care about >> the position, whereas your onsite matrix elements could potentially depend >> on other things (e.g. the lattice that the site is from) >> >> >> Happy Kwanting, >> >> >> Joe >> > -- Abbout Adel
