Hello,
I am trying to use alps version 2 to simulate a 2-D heisenberg spin ladder model with 2 different (ladder and rail) exchange strengths. In the example for a 1-D chain I changed the lattice to rectangular lattice but I guess that is not the right keyword. Is there an easy way to do this?
Thanks, John
Hello John,
Please take a look at the tutorials, where we show how to simulate a Heisenberg ladder. The lattice you should choose is "ladder" and the couplings (for a Heisenberg model) are called J0 on the chain and j1 on the rung.
Matthias
On Apr 4, 2007, at 5:41 PM, John Single wrote:
Hello,
I am trying to use alps version 2 to simulate a 2-D heisenbergspin ladder model with 2 different (ladder and rail) exchange strengths. In the example for a 1-D chain I changed the lattice to rectangular lattice but I guess that is not the right keyword. Is there an easy way to do this?
Thanks, John
Hello,
I am having a little difficulty understanding the tutorial for ALPS version 2. Is their a difference between the rectangular lattice and square lattice? If we set the coupling itself in 2d(J0 and J1) then does relative distance matter or is distance and coupling strength two separate factors that make up an effective coupling strength?
-Thanks, John
On 28 Jun 2007, at 08:57, John Single wrote:
Hello,
I am having a little difficulty understanding the tutorialfor ALPS version 2. Is their a difference between the rectangular lattice and square lattice? If we set the coupling itself in 2d(J0 and J1) then does relative distance matter or is distance and coupling strength two separate factors that make up an effective coupling strength?
-Thanks, John
We do not have any ALPS version 2 yet. Do you mean ALPS 1.2 or ALPS 1.3? The distance does not enter anywhere.
The way it works is that you define different bond types in the lattice (e.g. type 0,1,2) and then define Hamiltonian terms for each bond type. These terms can have different coupling constants (e.g. J0 and J1). There is a shortcut for that in version 1.3 and that's why I first need to know which version you are referring to.
Matthias
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