Comment on "Relaxation theory for perturbed many-body quantum systems
versus numerics and experiment"
- URL: http://arxiv.org/abs/2005.02681v1
- Date: Wed, 6 May 2020 09:29:41 GMT
- Title: Comment on "Relaxation theory for perturbed many-body quantum systems
versus numerics and experiment"
- Authors: Paul Secular
- Abstract summary: I argue that the discrepancy found is due to the quasi-local observable measured in the experiment being affected by a harmonic trapping potential.
I support my claim with quasi-exact numerics computed using a parallel time-evolving block decimation algorithm.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: In a recent Letter [Dabelow and Reimann, Phys. Rev. Lett. 124, 120602
(2020)], a perturbative relaxation theory is applied to the Bose-Hubbard model
and compared to data from a quantum simulator experiment [Trotzky et al. Nature
Phys 8, 325 (2012)]. In this Comment, I argue that the discrepancy found is due
to the quasi-local observable measured in the experiment being affected by a
harmonic trapping potential that is unaccounted for in the analytic
calculation. I support my claim with quasi-exact numerics computed using a
parallel time-evolving block decimation algorithm (TEBD), and show that the
relaxation theory gives accurate results in the correct limit when compared to
an appropriate local observable. Finally, I note that my numerics disagree with
the t-DMRG calculations of Trotzky et al. but give better qualitative agreement
with their experimental results.
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