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Tagged with spin-models spin-chains
66
questions
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How to compute the MPS representation for a sequence of asymptotically gapped quantum spin chains
Suppose I have a sequence of gapped, spin-$1/2$, translationally invariant quantum spin chains $\{H_1, H_2,H_3\cdots\}$ with interactions of range $\leq 2$ (i.e. no further than nearest-neighbors).
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- 985
4
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What is the relation between the Holstein-Primakoff Transformation and Bethe's Ansatz for the Heisenberg Ferromagnet?
Bethe's Ansatz is a method to find the eigenenergies and eigenstates of the Heisenberg ferromagnet (see also spin waves). For a general n-excitation state it involves solving rather complicated ...
- 11.6k
7
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1
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Goldstone mode as spin wave in 2D?
I'm trying to understand how Goldstone modes destroy long range order in 1D and 2D spin lattice.
I started with a spin chain, using 1D XY-model, which has continuous symmetry. $H=- \sum_{<i j>} ...
- 314
6
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Zero modes $a_j\sim e^{-\kappa j}$ in a semi-infinite quantum Ising chain?
As a way of analyzing the performance of quantum annealing, I've been studying quantum diffusion in fermionizable lattice models with zero modes.
In particular, the 1+1D quantum Ising model, semi-...
- 985
3
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1
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216
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How do we determine the statistics and spin of quasi-particles?
I am considering the Heisenberg XXZ model at the moment. In the literature it says that (in the $J\Delta\rightarrow\infty$ limit, i.e. the ferromagnetic Ising regime) one can either view low-energy ...
- 2,910
5
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Some limiting cases of the Heisenberg XXZ model (2/2)
NOTE: Because this was a long question I have split it up in two different questions!
For a course on quantum integrability I am reading these notes.
(Franchini: Notes on Bethe Ansatz Techniques. ...
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