Superluminal moving defects in the Ising spin chain
Quantum excitations in lattice systems always propagate at a finite maximum velocity. We probe this mechanism by considering a defect travelling at a constant velocity in the quantum Ising spin chain in transverse field. Independently of the microscopic details of the defect, we characterize the exp...
| Автори: | , |
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| Формат: | Journal article |
| Мова: | English |
| Опубліковано: |
American Physical Society
2018
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| _version_ | 1826258446296547328 |
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| author | Bastianello, A De Luca, A |
| author_facet | Bastianello, A De Luca, A |
| author_sort | Bastianello, A |
| collection | OXFORD |
| description | Quantum excitations in lattice systems always propagate at a finite maximum velocity. We probe this mechanism by considering a defect travelling at a constant velocity in the quantum Ising spin chain in transverse field. Independently of the microscopic details of the defect, we characterize the expectation value of local observables at large times and large distances from the impurity, where a Local Quasi Stationary State (LQSS) emerges. The LQSS is strongly affected by the defect velocity: for superluminal defects, it exhibits a growing region where translational invariance is spontaneously restored. We also analyze the behavior of the friction force exerted by the many-body system on the moving defect, which reflects the energy required by the LQSS formation. Exact results are provided in the two limits of extremely narrow and very smooth impurity. Possible extensions to more general free-fermion models and interacting systems are discussed |
| first_indexed | 2024-03-06T18:34:08Z |
| format | Journal article |
| id | oxford-uuid:0aa6d75f-c5e9-4b52-9584-5fe8c26f9250 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T18:34:08Z |
| publishDate | 2018 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | oxford-uuid:0aa6d75f-c5e9-4b52-9584-5fe8c26f92502022-03-26T09:24:56ZSuperluminal moving defects in the Ising spin chainJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:0aa6d75f-c5e9-4b52-9584-5fe8c26f9250EnglishSymplectic Elements at OxfordAmerican Physical Society2018Bastianello, ADe Luca, AQuantum excitations in lattice systems always propagate at a finite maximum velocity. We probe this mechanism by considering a defect travelling at a constant velocity in the quantum Ising spin chain in transverse field. Independently of the microscopic details of the defect, we characterize the expectation value of local observables at large times and large distances from the impurity, where a Local Quasi Stationary State (LQSS) emerges. The LQSS is strongly affected by the defect velocity: for superluminal defects, it exhibits a growing region where translational invariance is spontaneously restored. We also analyze the behavior of the friction force exerted by the many-body system on the moving defect, which reflects the energy required by the LQSS formation. Exact results are provided in the two limits of extremely narrow and very smooth impurity. Possible extensions to more general free-fermion models and interacting systems are discussed |
| spellingShingle | Bastianello, A De Luca, A Superluminal moving defects in the Ising spin chain |
| title | Superluminal moving defects in the Ising spin chain |
| title_full | Superluminal moving defects in the Ising spin chain |
| title_fullStr | Superluminal moving defects in the Ising spin chain |
| title_full_unstemmed | Superluminal moving defects in the Ising spin chain |
| title_short | Superluminal moving defects in the Ising spin chain |
| title_sort | superluminal moving defects in the ising spin chain |
| work_keys_str_mv | AT bastianelloa superluminalmovingdefectsintheisingspinchain AT delucaa superluminalmovingdefectsintheisingspinchain |