Dear Matthias,
thank you for your reply. Here below is the simplest input file, I just used spinless fermions instead of hardcore bosons:
LATTICE_LIBRARY="/opt/ALPS/lib/xml/lattices.xml" LATTICE="open ladder" MODEL_LIBRARY="/opt/ALPS/lib/xml/models.xml" MODEL="spinless fermions" CONSERVED_QUANTUMNUMBERS="N"
MAXSTATES=50 SWEEPS=4 L=10 t=0.01
mu0=1 mu1=10
MEASURE_LOCAL[density]=n { N_total=1}
My best regards, Giuliano
On Thu, 21 Feb 2013 07:37:32 +0400 Matthias Troyer troyer@phys.ethz.ch wrote:
Dear Giuliano,
you should not need to change the model since it should automatically use mu0 and mu1. To help us find the problem ypu report we would need your complete input files though.
Matthias
On Feb 21, 2013, at 2:46 AM, Giuliano Orso giuliano.orso@univ-paris-diderot.fr wrote:
Dear ALPS users, I am trying to simulate two-leg ladders models of say hardcore bosons. I need that the lower and upper leg have different chemical potentials, mu0 and mu1 respectively. How can I implement that efficiently ?
My naive idea:
- define a unit cell with two vertex (lower and upper site) plus
three edges (two horizontal+one vertical):
<UNITCELL name="ladderCell" dimension="1"> <VERTEX type="0"/> <VERTEX type="1"/> <EDGE type="0"> <SOURCE vertex="0" offset="0"/> <TARGET vertex="0" offset="1"/> </EDGE> <EDGE type="1"> <SOURCE vertex="0" offset="0"/> <TARGET vertex="1" offset="0"/> </EDGE> <EDGE type="2"> <SOURCE vertex="1" offset="0"/> <TARGET vertex="1" offset="1"/> </EDGE> </UNITCELL>
- The two-leg ladder is then a chain of such cells:
<LATTICEGRAPH name = "my open two leg ladder"> <FINITELATTICE> <LATTICE ref="chain lattice"/> <EXTENT dimension="1" size ="L"/> <BOUNDARY type="open"/> </FINITELATTICE> <UNITCELL ref="ladderCell"/> </LATTICEGRAPH>
- Finally I modify the model hamiltonian including the two
different chemical potentials defined as parameters:
<SITETERM type="0" site="i"> -mu0*n(i) </SITETERM> <SITETERM type="1" site="i"> -mu1*n(i) </SITETERM>
When I execute dmrg, the code gets stuck at "parsing task files ..." Could you please help me?
Thank you. My best regards, Giuliano