Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems
Quantum many-body scars (QMBS) are exceptional energy eigenstates of quantum many-body systems associated with violations of thermalization for special nonequilibrium initial states. Their various systematic constructions require fine-tuning of local Hamiltonian parameters. In this work, we demonstr...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2025-02-01
|
| Series: | Physical Review X |
| Online Access: | http://doi.org/10.1103/PhysRevX.15.011020 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832542868187643904 |
|---|---|
| author | Alessio Lerose Tommaso Parolini Rosario Fazio Dmitry A. Abanin Silvia Pappalardi |
| author_facet | Alessio Lerose Tommaso Parolini Rosario Fazio Dmitry A. Abanin Silvia Pappalardi |
| author_sort | Alessio Lerose |
| collection | DOAJ |
| description | Quantum many-body scars (QMBS) are exceptional energy eigenstates of quantum many-body systems associated with violations of thermalization for special nonequilibrium initial states. Their various systematic constructions require fine-tuning of local Hamiltonian parameters. In this work, we demonstrate that long-range interacting quantum spin systems generically host robust QMBS. We analyze spectral properties upon raising the power-law decay exponent α of spin-spin interactions from the solvable permutationally symmetric limit α=0. First, we numerically establish that, despite the fact that spectral signatures of chaos appear for infinitesimal α, the towers of α=0 energy eigenstates with large collective spin are smoothly deformed as α is increased and exhibit characteristic QMBS features. To elucidate the nature and fate of these states in larger systems, we introduce an analytical approach based on mapping the spin Hamiltonian onto a relativistic quantum rotor nonlinearly coupled to an extensive set of bosonic modes. We analytically solve for the eigenstates of this interacting impurity model by means of a novel polaron-type canonical transformation and show their self-consistent localization in large-spin sectors of the original Hamiltonian for 0<α<d (with d=spatial dimension of the lattice). Our theory unveils the stability mechanism of such QMBS for an arbitrary system size and predicts instances of its breakdown, e.g., near dynamical critical points or in the presence of semiclassical chaos, which we verify numerically in long-range quantum Ising chains. As a by-product, we find a predictive criterion for the presence or absence of heating under periodic driving for 0<α<d, beyond existing Floquet-prethermalization theorems. |
| format | Article |
| id | doaj-art-fce4e66795be4f0abb05cfce7bd94159 |
| institution | Kabale University |
| issn | 2160-3308 |
| language | English |
| publishDate | 2025-02-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review X |
| spelling | doaj-art-fce4e66795be4f0abb05cfce7bd941592025-02-03T15:15:42ZengAmerican Physical SocietyPhysical Review X2160-33082025-02-0115101102010.1103/PhysRevX.15.011020Theory of Robust Quantum Many-Body Scars in Long-Range Interacting SystemsAlessio LeroseTommaso ParoliniRosario FazioDmitry A. AbaninSilvia PappalardiQuantum many-body scars (QMBS) are exceptional energy eigenstates of quantum many-body systems associated with violations of thermalization for special nonequilibrium initial states. Their various systematic constructions require fine-tuning of local Hamiltonian parameters. In this work, we demonstrate that long-range interacting quantum spin systems generically host robust QMBS. We analyze spectral properties upon raising the power-law decay exponent α of spin-spin interactions from the solvable permutationally symmetric limit α=0. First, we numerically establish that, despite the fact that spectral signatures of chaos appear for infinitesimal α, the towers of α=0 energy eigenstates with large collective spin are smoothly deformed as α is increased and exhibit characteristic QMBS features. To elucidate the nature and fate of these states in larger systems, we introduce an analytical approach based on mapping the spin Hamiltonian onto a relativistic quantum rotor nonlinearly coupled to an extensive set of bosonic modes. We analytically solve for the eigenstates of this interacting impurity model by means of a novel polaron-type canonical transformation and show their self-consistent localization in large-spin sectors of the original Hamiltonian for 0<α<d (with d=spatial dimension of the lattice). Our theory unveils the stability mechanism of such QMBS for an arbitrary system size and predicts instances of its breakdown, e.g., near dynamical critical points or in the presence of semiclassical chaos, which we verify numerically in long-range quantum Ising chains. As a by-product, we find a predictive criterion for the presence or absence of heating under periodic driving for 0<α<d, beyond existing Floquet-prethermalization theorems.http://doi.org/10.1103/PhysRevX.15.011020 |
| spellingShingle | Alessio Lerose Tommaso Parolini Rosario Fazio Dmitry A. Abanin Silvia Pappalardi Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems Physical Review X |
| title | Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems |
| title_full | Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems |
| title_fullStr | Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems |
| title_full_unstemmed | Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems |
| title_short | Theory of Robust Quantum Many-Body Scars in Long-Range Interacting Systems |
| title_sort | theory of robust quantum many body scars in long range interacting systems |
| url | http://doi.org/10.1103/PhysRevX.15.011020 |
| work_keys_str_mv | AT alessiolerose theoryofrobustquantummanybodyscarsinlongrangeinteractingsystems AT tommasoparolini theoryofrobustquantummanybodyscarsinlongrangeinteractingsystems AT rosariofazio theoryofrobustquantummanybodyscarsinlongrangeinteractingsystems AT dmitryaabanin theoryofrobustquantummanybodyscarsinlongrangeinteractingsystems AT silviapappalardi theoryofrobustquantummanybodyscarsinlongrangeinteractingsystems |