I have posted these messages. They have no answers. Please take some time to answer them as I am student and answers from your part are very important to me. I am waiting
Dear alps team,
I am reproducing the spectrum on page 3 of this paper, which is the Lowest spectrum of the hubbard model on a plaquette. Eigenstates are labelled by total spin S and plaquette momentum Qx,Qy = 0, ?.
author = "Ehud Altman and Assa Auerbach",
title = "Plaquette Boson -- Fermion Model of Cuprates",
condmat = "cond-mat/0108087",
I have written the following program
LATTICE_LIBRARY="/temp/ALPS/xml/lattices.xml"
MODEL_LIBRARY="/temp/ALPS/xml/models.xml"
MODEL="fermion Hubbard"
LATTICE="anisotropic square lattice"
L=2
W=2
U=1000000000
CONSERVED_QUANTUMNUMBERS="N,Sz"
{N_total=3; Sz_total=0.5; t=1.0;}
{N_total=3; Sz_total=1.5; t=1.0;}
my results with fulldiag are not matching with the paper. Probably I am not mentiong the total_spin total_particle or conserved quantum number properly.
i recognize 0 holes as 4 particles, 1 holes as 3 particles and 2 holes as 2 particles in 2 by 2 pluquette.
Please take some time to correct me.
Best Regards
Khalid loane
------------------------------
Message: 3
Date: Thu, 16 Apr 2009 11:55:03 -0700 (PDT)
From: khalid hassan <mkhloane(a)yahoo.com>
Subject: [ALPS-users] repharasing the lowest spectrum fermion hubbard
question
To: alps users alps users <comp-phys-alps-users(a)phys.ethz.ch>
Message-ID: <178183.68074.qm(a)web59405.mail.ac4.yahoo.com>
Content-Type: text/plain; charset=us-ascii
Dear alps team
i want ti rephrase my question to make it more precise
I have
fermion hubbard model
2 by 2 square plaquette
total number of particle = 3
total spin S= 1/2
need ground state energy
which will be plaquette momentum (Pi,0) and (0, Pi) degenerate
The program I wrote is giving plaquette momentum (0,0) and (0,Pi) as ground state, which is wrong as seen in the paper.
My statements are under. Please correct my statements. I tried very much but could not find the correct ground states. It is trivial task as written in paper.
LATTICE_LIBRARY="/temp/ALPS/xml/lattices.xml";
MODEL_LIBRARY="/temp/ALPS/xml/models.xml";
MODEL="fermion Hubbard";
LATTICE="anisotropic square lattice";
L=2;
W=2;
Sz_total=0.5;
U=0.5;
CONSERVED_QUANTUMNUMBERS="N,Sz"
N_total=3
{ t=1.0;}
Best Regards
Khalid Loane
Dear alps team,
I am reproducing the spectrum on page 3 of this paper, which is the Lowest spectrum of the hubbard model on a plaquette. Eigenstates are labelled by total spin S and plaquette momentum Qx,Qy = 0, ?.
author = "Ehud Altman and Assa Auerbach",
title = "Plaquette Boson -- Fermion Model of Cuprates",
condmat = "cond-mat/0108087",
I have written the following program
LATTICE_LIBRARY="/temp/ALPS/xml/lattices.xml"
MODEL_LIBRARY="/temp/ALPS/xml/models.xml"
MODEL="fermion Hubbard"
LATTICE="anisotropic square lattice"
L=2
W=2
U=1000000000
CONSERVED_QUANTUMNUMBERS="N,Sz"
{N_total=3; Sz_total=0.5; t=1.0;}
{N_total=3; Sz_total=1.5; t=1.0;}
my results with fulldiag are not matching with the paper. Probably I am not mentiong the total_spin total_particle or conserved quantum number properly.
i recognize 0 holes as 4 particles, 1 holes as 3 particles and 2 holes as 2 particles in 2 by 2 pluquette.
Please take some time to correct me.
Best Regards
Khalid loane