Search found 10 matches
- 14 Jul 2022, 00:53
- Forum: HowTos and FAQ for TeNPy
- Topic: Different Energy measures giving mixed results
- Replies: 1
- Views: 2579
Different Energy measures giving mixed results
Hi, I'm looking at the time-evolution of a product state under a time-dependent Hamiltonian using iTEBD. For certain simulation parameters, it's the case that when I measure the bond-energy, using M.bond_energies() for a model M, that energy is different for the two bonds. This is an issue in my res...
- 22 Apr 2022, 19:11
- Forum: HowTos and FAQ for TeNPy
- Topic: Charge Info for Z3 symmetry in 3-state Potts Model
- Replies: 3
- Views: 4960
Re: Charge Info for Z3 symmetry in 3-state Potts Model
Great, thank you Johannes!
- 20 Apr 2022, 22:22
- Forum: HowTos and FAQ for TeNPy
- Topic: Charge Info for Z3 symmetry in 3-state Potts Model
- Replies: 3
- Views: 4960
Charge Info for Z3 symmetry in 3-state Potts Model
Hi, I'm trying to implement the 3-state Potts Model, with Hamiltonian H = \sum_i \Omega^{\dagger}_i\Omega_{i+1} + \Omega_i\Omega^{\dagger}_{i+1} + \sum_i [\Gamma_i^{(1)} + \Gamma_i^{(2)}] with \Omega_i = diag(1, e^{i2\pi/3}, e^{-i2\pi/3}) And \Gamma_i^{(1)} is a cyclic permutation of the 3 basis sta...
- 18 Aug 2021, 22:25
- Forum: Algorithms
- Topic: iTDVP and canonical forms
- Replies: 2
- Views: 13395
iTDVP and canonical forms
I'm working on developing an iTDVP algorithm using TeNPy. I'm able to recycle most of the aspects from the finite TDVP code, but there are some issues when trying to insert the updated tensors to for an updated MPS. Essentially, we have a 1-site and 0-site effective Hamiltonian that we use to update...
- 16 Jun 2021, 23:42
- Forum: HowTos and FAQ for TeNPy
- Topic: Singular Values as np_conserved
- Replies: 1
- Views: 2833
Singular Values as np_conserved
I'm trying to implement the iTDVP algorithm following https://scipost.org/SciPostPhysLectNotes.7/pdf In doing this, I need to update both the center site tensor using the '1-site' Hamiltonian, as well as the center site singular values using the '0-site' Hamiltonian. In order to do this, I'd like to...
- 09 Jun 2021, 19:43
- Forum: Algorithms
- Topic: Question about iTDVP
- Replies: 1
- Views: 11979
Question about iTDVP
I'm trying to implement the infinite TDVP algorithm based on these notes https://arxiv.org/abs/1810.07006 It seems like these are the main steps: 1) Find the left and right environments 2) Use these to create effective Hamiltonians 0, and 1 site. 3) Integrate the TDVP equations to update the MPS ten...
- 04 May 2021, 00:55
- Forum: HowTos and FAQ for TeNPy
- Topic: Dynamics with Segment Boundary Conditions
- Replies: 0
- Views: 63391
Dynamics with Segment Boundary Conditions
I'm looking to study time-dependent two-point correlation functions following the prescription laid out in https://arxiv.org/abs/1207.0652 It seems like 'segment' boundary condition is what I'm looking for, but I'm confused on how to utilize this. What I want to do is use iDMRG to find the ground st...
- 28 Apr 2021, 00:48
- Forum: HowTos and FAQ for TeNPy
- Topic: Correlation function with infinite boundary conditions
- Replies: 4
- Views: 4459
Re: Correlation function with infinite boundary conditions
Great, I was thinking it's what I'm looking for. I have another possibly naive question. How do I actually use "segment"? I want to use infinite boundary conditions to find the ground state with DMRG, but then I want to transition to segment for the time evolution. So how would I go about ...
- 27 Apr 2021, 02:26
- Forum: HowTos and FAQ for TeNPy
- Topic: Correlation function with infinite boundary conditions
- Replies: 4
- Views: 4459
Re: Correlation function with infinite boundary conditions
I guess I forgot to mention explicitly that I want to study dynamics, so <Sz(x,t)Sz(0,0)> say. It seems like in order to time evolve Sz|psi>, I need to strictly work at finite system size, since the state is no longer translationally invariant. However, to eliminate boundary effects, one can use edg...
- 21 Apr 2021, 00:30
- Forum: HowTos and FAQ for TeNPy
- Topic: Correlation function with infinite boundary conditions
- Replies: 4
- Views: 4459
Correlation function with infinite boundary conditions
Hi, I'm new to TenPy, and I'm looking to compute correlation functions using infinite boundary conditions, based on this paper https://arxiv.org/abs/1207.0652 What I'm wondering is if this functionality is already baseline in TenPy? I'm thinking the 'segment' boundary condition might be what I'm loo...