Local quantum quenches in critical one-dimensional systems: entanglement, the Loschmidt echo, and light-cone effects

Details Local quantum quenches in critical one-dimensional systems: entanglement, the Loschmidt echo, and light-cone effects Local quantum quenches in critical one-dimensional systems: entanglement, the Loschmidt echo, and light-cone effects

2011-05-24

arxiv.org/abs/1105.4846v3

J. Stat. Mech. (2011) P08019

Physics

Condensed Matter

Statistical Mechanics

28 pages, 20 figures. v3: published version

Scientific paper

10.1088/1742-5468/2011/08/P08019

We study a particular type of local quench in a generic quantum critical one-dimensional system, using conformal field theory (CFT) techniques, and providing numerical checks of the results in free fermion systems. The system is initially cut into two subsystems $A$ and $B$ which are glued together at time $t=0$. We study the entanglement entropy (EE) between the two parts $A$ and $B$, using previous results by Calabrese and Cardy, and further extending them. We also study in detail the (logarithmic) Loschmidt echo (LLE). For finite-size systems both quantities turn out to be (almost) periodic in the scaling limit, and exhibit striking light-cone effects. While these two quantities behave similarly immediately after the quench---namely as $c/3 \log t$ for the EE and $c/4 \log t$ for the LLE---, we observe some discrepancy once the excitations emitted by the quench bounce on the boundary and evolve within the same subsystem $A$ (or $B$). The decay of the EE is then non-universal, as noticed by Eisler and Peschel. On the contrary, we find that the evolution of the LLE is less sensitive than the EE to non-universal details of the model, and is still accurately described by our CFT prediction. To further probe these light-cone effects, we also introduce a variant of the Loschmidt echo specifically constructed to detect the excitations emitted just after the quench.

Affiliated with

Also associated with

No associations

Rating

Local quantum quenches in critical one-dimensional systems: entanglement, the Loschmidt echo, and light-cone effects does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Local quantum quenches in critical one-dimensional systems: entanglement, the Loschmidt echo, and light-cone effects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Local quantum quenches in critical one-dimensional systems: entanglement, the Loschmidt echo, and light-cone effects will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-516944