Search found 6 matches

by jamarks
17 Jun 2020, 03:38
Forum: HowTos and FAQ for TeNPy
Topic: Bipartitioning infinite MPS into 2 semi-infinite chains
Replies: 11
Views: 1104

Re: Bipartitioning infinite MPS into 2 semi-infinite chains

Hi Johannes, Thank you so much! Using charge_sector = None and pulling the most recent commit from TeNPy, I am now able to extract both the Polarization and the TM eigs when using charges='same'. Also switched to using DMRG for the ground state as you suggested. Everything works perfectly Thanks for...
by jamarks
15 Jun 2020, 22:02
Forum: HowTos and FAQ for TeNPy
Topic: Bipartitioning infinite MPS into 2 semi-infinite chains
Replies: 11
Views: 1104

Re: Bipartitioning infinite MPS into 2 semi-infinite chains

Thanks again for the reply. I fully recognize the different between the 'adiabatic' evolution that is entailed by charge pumping, and the real time evolution that I am doing. The basic idea I am looking at is quenches in order-obstructed SPT phases. As such, I am interested in looking at the evoluti...
by jamarks
12 Jun 2020, 15:08
Forum: HowTos and FAQ for TeNPy
Topic: Bipartitioning infinite MPS into 2 semi-infinite chains
Replies: 11
Views: 1104

Re: Bipartitioning infinite MPS into 2 semi-infinite chains

I'm using TEBD to get the ground state, and to do the real-time evolution. Here's the model definition: from tenpy.models.model import NearestNeighborModel, CouplingMPOModel from tenpy.models.lattice import Site, Chain from tenpy.networks.site import FermionSite, GroupedSite class SSHIntModel(Coupli...
by jamarks
10 Jun 2020, 14:31
Forum: HowTos and FAQ for TeNPy
Topic: Bipartitioning infinite MPS into 2 semi-infinite chains
Replies: 11
Views: 1104

Re: Bipartitioning infinite MPS into 2 semi-infinite chains

Hi Johannes, Thanks again for the reply. The issue is that I'm using GroupedSite, and in addition to the Polarization, I am also interested in obtaining the eigenvalues of the transfer matrix. I've found that when I define the GroupedSite using charges = 'same', the TransferMatrix ends up having no ...
by jamarks
01 Jun 2020, 14:18
Forum: HowTos and FAQ for TeNPy
Topic: Bipartitioning infinite MPS into 2 semi-infinite chains
Replies: 11
Views: 1104

Re: Bipartitioning infinite MPS into 2 semi-infinite chains

Hi Johannes, Thank you so much for your helpful and detailed response. I am indeed aware that the polarization is only defined modulo 1, but would still like to be able to compute this quantity. The code you reference, which demonstrates flux pumping, (and the function 'average_charge',) is close to...
by jamarks
22 May 2020, 21:23
Forum: HowTos and FAQ for TeNPy
Topic: Bipartitioning infinite MPS into 2 semi-infinite chains
Replies: 11
Views: 1104

Bipartitioning infinite MPS into 2 semi-infinite chains

I'm trying to compute the Resta Polarization of a Fermionic SSH chain according to the method described in https://arxiv.org/pdf/1810.07043.pdf equations 13-15. In particular, I need to compute 'particle imbalance' by partitioning the system into 2 semi-infinite chains, and tracing out one of these ...