Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System
When a qubit or spin interacts with others under a many-body Hamiltonian, the information it containsprogressively scrambles. Here, nuclear spins of an adamantane crystal are used as a quantum simulator tomonitor such dynamics through out-of-time-order correlators, while a Loschmidt echo (LE) asses...
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| Format: | Article |
| Language: | English |
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American Physical Society (APS)
2020
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| Online Access: | https://hdl.handle.net/1721.1/124332 |
| _version_ | 1826193164593004544 |
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| author | Wei, K. X. Cappellaro, Paola |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Wei, K. X. Cappellaro, Paola |
| author_sort | Wei, K. X. |
| collection | MIT |
| description | When a qubit or spin interacts with others under a many-body Hamiltonian, the information it containsprogressively scrambles. Here, nuclear spins of an adamantane crystal are used as a quantum simulator tomonitor such dynamics through out-of-time-order correlators, while a Loschmidt echo (LE) asses howweak perturbations degrade the information encoded in these increasingly complex states. Bothobservables involve the implementation of a time-reversal procedure which, in practice, involves invertingthe sign of the effective Hamiltonian. Our protocols use periodic radio frequency pulses to modulate thenatural dipolar interaction implementing a Hamiltonian that can be scaled down at will. Meanwhile,experimental errors and strength of perturbative terms remain constant and can be quantified through theLE. For each scaling factor, information spreading occurs with a timescale,T₂, inversely proportional to thelocal second moment of the Hamiltonian. We find that, when the reversible interactions dominate over theperturbations, the information scrambled among up to10² spins can still be recovered. However, we findthat the LE decay rate cannot become smaller than a critical value 1/T₃~(0.15±0.02)=T₂, which onlydepends on the interactions themselves, and not on the perturbations. This result shows the emergence of aregime of intrinsic irreversibility in accordance to a central hypothesis of irreversibility, hinted fromprevious experiments. |
| first_indexed | 2024-09-23T09:35:03Z |
| format | Article |
| id | mit-1721.1/124332 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T09:35:03Z |
| publishDate | 2020 |
| publisher | American Physical Society (APS) |
| record_format | dspace |
| spelling | mit-1721.1/1243322022-09-30T15:27:56Z Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System Wei, K. X. Cappellaro, Paola Massachusetts Institute of Technology. Department of Physics Massachusetts Institute of Technology. Research Laboratory of Electronics Massachusetts Institute of Technology. Department of Nuclear Science and Engineering General Physics and Astronomy When a qubit or spin interacts with others under a many-body Hamiltonian, the information it containsprogressively scrambles. Here, nuclear spins of an adamantane crystal are used as a quantum simulator tomonitor such dynamics through out-of-time-order correlators, while a Loschmidt echo (LE) asses howweak perturbations degrade the information encoded in these increasingly complex states. Bothobservables involve the implementation of a time-reversal procedure which, in practice, involves invertingthe sign of the effective Hamiltonian. Our protocols use periodic radio frequency pulses to modulate thenatural dipolar interaction implementing a Hamiltonian that can be scaled down at will. Meanwhile,experimental errors and strength of perturbative terms remain constant and can be quantified through theLE. For each scaling factor, information spreading occurs with a timescale,T₂, inversely proportional to thelocal second moment of the Hamiltonian. We find that, when the reversible interactions dominate over theperturbations, the information scrambled among up to10² spins can still be recovered. However, we findthat the LE decay rate cannot become smaller than a critical value 1/T₃~(0.15±0.02)=T₂, which onlydepends on the interactions themselves, and not on the perturbations. This result shows the emergence of aregime of intrinsic irreversibility in accordance to a central hypothesis of irreversibility, hinted fromprevious experiments. 2020-03-25T18:15:13Z 2020-03-25T18:15:13Z 2020-01-21 2020-02-20T18:38:43Z Article http://purl.org/eprint/type/JournalArticle 0031-9007 1079-7114 https://hdl.handle.net/1721.1/124332 Sánchez, C. M. et al. "Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System." Physical review letters 124 (2020):030601 © 2020 The Author(s) en 10.1103/physrevlett.124.030601 Physical review letters Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society (APS) APS |
| spellingShingle | General Physics and Astronomy Wei, K. X. Cappellaro, Paola Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System |
| title | Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System |
| title_full | Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System |
| title_fullStr | Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System |
| title_full_unstemmed | Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System |
| title_short | Perturbation Independent Decay of the Loschmidt Echo in a Many-Body System |
| title_sort | perturbation independent decay of the loschmidt echo in a many body system |
| topic | General Physics and Astronomy |
| url | https://hdl.handle.net/1721.1/124332 |
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