English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We revisit the so-called folded XXZ model, which was treated earlier by twoindependent research groups. We argue that this spin-1/2 chain is one of thesimplest quantum integrable models, yet it has quite remarkable physicalproperties. The particles have constant scattering lengths, which leads to asimple treatment of the exact spectrum and the dynamics of the system. TheHilbert space of the model is fragmented, leading to exponentially largedegeneracies in the spectrum, such that the exponent depends on the particlecontent of a given state. We provide an alternative derivation of theHamiltonian and the conserved charges of the model, including a newinterpretation of the so-called "dual model" considered earlier. We alsoconstruct a non-local map that connects the model with the Maassarani-Mathieuspin chain, also known as the SU(3) XX model. We consider the exact solution ofthe model with periodic and open boundary conditions, and also derive multipledescriptions of the exact thermodynamics of the model. We consider quantumquenches of different types. In one class of problems the dynamics can betreated relatively easily: we compute an example for the real time dependenceof a local observable. In another class of quenches the degeneracies of themodel lead to the breakdown of equilibration, and we argue that they can leadto persistent oscillations. We also discuss connections with the $T\bar T$- andhard rod deformations known from Quantum Field Theories.

An integrable spin chain with Hilbert space fragmentation and solvable real time dynamics