Hi, Fernando,
Assuming that you use DMRG simulation since you specify 'MAXSTATES'.
(2014/06/12 0:10), Fernando Iemini wrote:
I've using the ''alternative fermion Hubbard'' model, with open boundary conditions, and analyzing its single-particle correlations, <cdag_up:c_up>. I'm not being able however to compute these observables for larger lattices, e.g., L=~160. I'm getting a "segmentation fault" message, does anybody know why is happening this error, maybe due to memory? If so, what would be good parameters in order to avoid it?
Here is the script i'm using:
LATTICE="open chain lattice" MODEL="alternative fermion Hubbard" CONSERVED_QUANTUMNUMBERS="N,Sz,Nup,Ndown" N_total=160 Sz_total=0 Nup_total=80 Ndown_total=80 mu=0 t=1 NUMBER_EIGENVALUES=1 L=160 MAXSTATES=100 MEASURE_CORRELATIONS[cdag_up c_up]="cdag_up:c_up" {U = 9.000000e-01,V=5.500000e-01,TRUNCATION_ERROR=1e-7}
This is memory issue. The problem is that 'MEASURE_CORRELATIONS' collects all pair sites. Observing ~10000 measurements costs too much memory.
Not tested, but I believe that you can avoid this issue by tweaking models.xml and lattices.xml. Change the name of some specific operator and just calculating between them.