All Questions
Tagged with spin-models spin-chains
66
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Is there a relationship between spin correlation and entanglement entropy?
Can someone explain whether there is a connection between spin correlation in say a 1D Heisenberg chain and its entanglement entropy? I'd say, albeit naively, that there is just from their concepts. ...
- 11
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Writing the Random Matrix model corresponding to any physical hamitonian model
I am an amateur in Random Matrix Theory (RMT). In RMT, we start with ensemble of a random matrices of a certain symmetry classes (GOE, GUE..) to find the various distribution of our interest, e.g.- ...
- 244
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How can I actually get to the AKLT state from a product state in finite depth?
I'm currently learning about symmetry-protected topological phases in one dimension. The ground state of the AKLT model provides one such example. In particular, the AKLT state for any length $L$ ...
- 2,292
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How to take into account finite temperature in transverse Ising chain?
A similar question has already been asked here
What I'm wondering is how to take into account finite temperature in the transverse Ising chain and see how that affects the magnetization. The reason ...
- 741
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How do boundary conditions change during a spin transformation?
I am currently reading the following review paper:
(1) Two Dimensional Model as a Soluble Problem for Many Fermions by Schultz et. al.
Equation (3.2), which is reproduced below, introduces the Jordan-...
user261609
2
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1
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223
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Jordan-Wigner Transformations on fermionic system
I've been trying to use Jordan-Wigner Transformations on a given fermionic Hamiltonian. The given Hamiltonian is: $$ \hat{H}= -\sum_{m=1}^{N}(J_z \hat{S}_{m}^{z} \hat{S}_{m+1}^{z} + \frac{J_{\perp}}{2}...
- 23
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204
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Parity of XYZ model ground state
I am considering the XYZ Hamiltonian (with PBC) $$\widehat{H}_{\mathrm{XYZ}}=\sum_{i=1}^{N} \left(\hat{\sigma}_{i}^{x} \hat{\sigma}_{i+1}^{x}+J_{y}\hat{\sigma}_{i}^{y} \hat{\sigma}_{i+1}^{y}+J_{z}\hat{...
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110
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Writing down a Hamiltonian that couples spin and phonons
I am studying spin dynamics and am trying to write down a Hamiltonian that couples the spins with the phonons. I have the following interacting spin Hamiltonian
$$H_{s}=\sum h_{i}S_{i}+H_{\text{...
- 21
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69
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Time evolution of spin with Anti-symmetric (Dzyaloshinkii-Moriya) interaction
I am trying to simulate the time evolution of a spin in spin chain interacting via Dzyaloshinkii-Moriya interaction. The Hamiltonian is of the form
$$H_{A}=J_{A}\sum_{i}(S^{x}_{i}S_{i+1}^{y}-S^{x}_{i+...
- 21
4
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230
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Heisenberg equation of motion and continuum limit
Given the quite simple Hamiltonian
$$\hat{\mathcal{H}}=\sum_n\big(\hat{S}_n^+\hat{S}^-_{n+1}+\hat{S}_n^-\hat{S}^+_{n+1}\big)$$
on a 1D spin chain, it basically interchanges two spins lying next to ...
- 294
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487
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Commutator of Hamiltonian and the spin sum
For a 1-D Heisenberg quantum spin chain the Hamiltonian is given by:
$$H=-\sum_{j=0}^{N-1} J_{i,i+1}\boldsymbol{\sigma}_j^i \cdot\boldsymbol{\sigma}_{j+1}^i -\sum_{j=0}^{N}h_j\sigma_j^z$$
where $\...
- 11
3
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2
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652
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Jordan-Wigner transformation for lattice models without $U(1)$ symmetry
The Jordan-Wigner transformation is a powerful approach to studying one-dimensional spin models. The following dictionary between spin operators and creation/annihilation operators for fermions allows ...
- 759
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Why is $\sum_{i=0}^N S_i^z S_{i+1}^z |\uparrow ... \downarrow_n ... \uparrow \rangle = \frac{1}{4}(N-4)$?
I am following these (http://edu.itp.phys.ethz.ch/fs13/int/SpinChains.pdf) lecture notes and I can't understand why given the following XXX Heisenberg hamiltonian
$$
\mathcal{H}=\frac{J N}{4}-J \sum_{...
- 1,544
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75
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Antiferromagnetic chain from Altland/Simons book (p.81)
In Condensed Matter Field Theory (2nd edition) by Altland/Simons there considered antiferromagnetic chain with Hamiltonian:
$$H = J\sum_{<n,m>} S_nS_m = J\sum_{<n,m>}[S^{z}_n S^{z}_m + \...
- 341
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Is there any study about using DMRG to simulate two spin chains coupled at only several sites on each chain?
Is there any study about the DMRG simulation of such kind of systems?
or
Each blue site is a spin, for example. Only one or several spins on each chain are coupled.
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