Hi Alex,

On Feb 16, 2013, at 2:35 AM, Alex Petrescu tpetresc@gmail.com wrote:

Hello,

Is it possible to implement gauge fields for the lattice models? More explicitly, can one define:

• bond operators which are a function of the position of the source and target sites

This is possible just by giving, e.g. the horizontal and vertical bonds a different type.

• bond operators which are a function of the order in which the source and target sites are specified (say the source site is of type 1, and the target site is of type 2, then there should be a phase Exp[i phi], and conjugate if the source is of type 2 and target of type 1.)

I am not sure about all QMC codes, but the ED and DMRG codes can do that. The bonds are "directed" edges in the graph.

Matthias