On Mar 4, 2013, at 5:08, Bo-Nan JIANG bonanjiang@gmail.com wrote:
Hi,all This is my interpretation of the relationship between vertex, edge and operator. Am I right? Considering 1D Kondo-Heisenberg model, for example: (1) I shall have two types of vertices - spin and fermion; (2) Three types of edges - fermion to fermion, fermion to spin and spin to spin (considering superexchange interaction between spins); (3) For operators, I shall have - type0 fermion_hop(i,j) related to fermion to fermion edge, type1 exchange(i,j) related to fermion to spin (Kondo-exchange interaction) and type2 exchange(i,j) (superexchange); If I am right, does that mean the number of types of bond operators should be the same as the number of types of edges defined in the unitcell?
Yes
The other question is: in the unitcell of this simple 1D Kondo-Heisenberg model, I have two-type vertices and three different types of edges, but I do not define the coordinates as your online example "A complex example" in section "How to specify graphs corresponding to a lattice with a unit cell", then is the unitcell which I define 1D or 2D? I think it is 2D, am I right?
No, still 1D since you will have a 1 d chain of unit cells.
Bo-Nan
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