Search found 4 matches

by pfliang
30 Mar 2022, 06:08
Forum: HowTos and FAQ for TeNPy
Topic: iDMRG sweep schedule
Replies: 3
Views: 3181

Re: iDMRG sweep schedule

Thanks for the nice explanation! Now I roughly understand how idmrg is implemented in tenpy. I have two further questions: 1. For idmrg, after 10 sweeps (which is the default value of 'N_sweeps_check') with optimization, 5 more sweeps without optimization are performed. Since each sweep enlarge the ...
by pfliang
09 Mar 2022, 11:24
Forum: HowTos and FAQ for TeNPy
Topic: iDMRG sweep schedule
Replies: 3
Views: 3181

iDMRG sweep schedule

Hello, I am trying to read your implementation of iDMRG and got confused about how you do sweeps and update left and right environments. For a unit cell of 4 spins, let's say, I can see for one round the code uses updating rules like (true,true)X2, (true,false)X2, (true,true)X2, (false, true)X2. Cou...
by pfliang
30 Mar 2021, 03:12
Forum: HowTos and FAQ for TeNPy
Topic: Get excited states in different symmetry sectors
Replies: 3
Views: 2222

Re: Get excited states in different symmetry sectors

Thanks a lot for the reply. I did a few tests, it's exactly as what you said. But I found using single site DMRG gives me wrong results. Can you explain why it is so? See the code below. def test_dmrg_excited(eps=1.e-12): L, g = 8, 1.3 bc = 'finite' model_params = dict(L=L, J=1., g=g, bc_MPS=bc, con...
by pfliang
29 Mar 2021, 19:28
Forum: HowTos and FAQ for TeNPy
Topic: Get excited states in different symmetry sectors
Replies: 3
Views: 2222

Get excited states in different symmetry sectors

Hello,

While I was looking at the function test_dmrg_excited in test_dmry.py, I noticed the excited states searched by tenpy are all in the same symmetry sector.
I wonder if there is a way to get excited states in other symmetry sectors with tenpy?