Dear all,

I am trying to understand how to use the qmc codes from ALPS to get some local observables from lattice models. If I understand it correctly, the way qmc codes work is in imaginary time and in that representation one can measure thermodynamic quantities. In the case of dynamical quantities(by this I mean dynamical susceptibilities), the results in imaginary time have to be analytically continued back to the real time axis and then evaluated. This is done usually, from what I gather from the literature, using maximum entropy methods. I have read through the tutorials on the alps website and the different slides by the ALPS creators that I found on google and I haven't found any example of the last type of calculations. Neither how to "tell" ALPS to measure a non-averaged susceptibility or how to analytically continue it to the real axis.

Is it possible with ALPS as it is or do I need to write my own c++ code, based on ALPS, to access that kind of information? If it is possible, could someone tell me where I can find documentation on how to do it specifically with ALPS?

Kind regards, Paco Cordobes