Hello all.
As a test case for Alps 2, we are running fulldiag for a 1D Hubbard model with only three lattice sites,
res = pyalps.runApplication('fulldiag',input_file,writexml=True) data = pyalps.loadEigenstateMeasurements(pyalps.getResultFiles(prefix='parm1'))
and are measuring
'MEASURE_CORRELATIONS[Sx Sx]' : "Sx:Sx", 'MEASURE_CORRELATIONS[Sz Sz]' : "Sz:Sz", 'MEASURE_CORRELATIONS[NupNdw]' : "Nup:Ndown", 'MEASURE_CORRELATIONS[NupNup]' : "Nup:Nup",
and everything seems to check out fine, except of <Sx Sx>. We see that the site operator Sx is correctly defined from Splus and Sminus, but is this the way to use it in the measurements?
Cheers, Miguel
On 16 Mar 2011, at 10:23, Miguel Dias Costa wrote:
Hello all.
As a test case for Alps 2, we are running fulldiag for a 1D Hubbard model with only three lattice sites,
res = pyalps.runApplication('fulldiag',input_file,writexml=True) data = pyalps.loadEigenstateMeasurements(pyalps.getResultFiles(prefix='parm1'))
and are measuring
'MEASURE_CORRELATIONS[Sx Sx]' : "Sx:Sx", 'MEASURE_CORRELATIONS[Sz Sz]' : "Sz:Sz", 'MEASURE_CORRELATIONS[NupNdw]' : "Nup:Ndown", 'MEASURE_CORRELATIONS[NupNup]' : "Nup:Nup",and everything seems to check out fine, except of <Sx Sx>. We see that the site operator Sx is correctly defined from Splus and Sminus, but is this the way to use it in the measurements?
Cheers, Miguel
You will need to define SPlus and Sminus for the Hubbard model. Dod you do that?
Matthias
Dear Matthias,
On 03/16/2011 09:46 AM, Matthias Troyer wrote:
You will need to define SPlus and Sminus for the Hubbard model. Dod you do that?
I thought they were already defined in the "fermion" basis, but I suppose those are particle operators and I'm trying to measure a site property... If I define
<SITEOPERATOR name="Splus" site="x"> cdag_up(x)*c_down(x) </SITEOPERATOR>
<SITEOPERATOR name="Sminus" site="x"> cdag_down(x)*c_up(x) </SITEOPERATOR>
before
<SITEOPERATOR name="Sx" site="x"> 1/2*(Splus(x)+Sminus(x)) </SITEOPERATOR>
I get the expected result. Is this what you meant?
Cheers, Miguel
Yes, that will do it
Matthias
On Mar 21, 2011, at 5:58 AM, Miguel Dias Costa wrote:
Dear Matthias,
On 03/16/2011 09:46 AM, Matthias Troyer wrote:
You will need to define SPlus and Sminus for the Hubbard model. Dod you do that?
I thought they were already defined in the "fermion" basis, but I suppose those are particle operators and I'm trying to measure a site property... If I define
<SITEOPERATOR name="Splus" site="x"> cdag_up(x)*c_down(x) </SITEOPERATOR>
<SITEOPERATOR name="Sminus" site="x"> cdag_down(x)*c_up(x) </SITEOPERATOR>
before
<SITEOPERATOR name="Sx" site="x"> 1/2*(Splus(x)+Sminus(x)) </SITEOPERATOR>
I get the expected result. Is this what you meant?
Cheers, Miguel
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