Dear Hosein, You are creating a system with essentially all possible hoppings. These will take a considerable computational cost regardless of what you do. Try limiting the number of hoppings to only a few nearest neighbors per site.
Best, Anton On Wed, 14 Aug 2019 at 09:40, Khani Hosein <[email protected]> wrote: > > Dear developers, > I constructed Lat_A and Lat_B for a system. > A1,A2=Lat_A.sublattices > B1,B2=Lat_B.sublattices > I want to set hoppings between Lat_A and Lat_B, and the hoppings are > dependent on the site position.Every atom of Lat_A is coupled to all the > atoms in Lat_B. > > Now I have tried it like this : > def coupling(site1,site2): > xp1,yp1=site1.pos > xp2,yp2=siye2.pos > return t*sqrt((xp1-xp2)**2+(yp1-yp2)**2)/d > > for i in range(100): > for j in range(100): > sys[kwant.builder.HoppingKind(( i, j), A1, B1)] = coupling > sys[kwant.builder.HoppingKind(( i, j), A1, B2)] = coupling > sys[kwant.builder.HoppingKind(( i, j), A2, B1)] = coupling > sys[kwant.builder.HoppingKind(( i, j), A2, B2)] = coupling > > It can not work because it take too long to do the calculations. I am > considering a bilayer system but rotations are considered, for example a > twisted bilayer graphene. Could you please help me to solve this problem? > Regards, > Hosein Khani
