Stability of quantum many-body scars on PXP model
- URL: http://arxiv.org/abs/2407.14691v1
- Date: Fri, 19 Jul 2024 22:39:15 GMT
- Title: Stability of quantum many-body scars on PXP model
- Authors: Alessandra Chioquetta, Raphael Campos Drumond,
- Abstract summary: We numerically compute the fidelity and average correlations to monitor the state evolution and to identify revivals.
Results indicate that, on the one hand, the entanglement entropy of PXP scars exhibit great sensitivity.
Other scar signatures, such as the revivals of states having large overlap with scars, show remarkable robustness.
- Score: 49.1574468325115
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We investigate the stability of quantum many-body scars under perturbations, within the PXP model. We numerically compute the fidelity and average correlations to monitor the state evolution and to identify revivals. The results indicate that, on the one hand, the entanglement entropy of PXP scars exhibit great sensitivity, in the sense that their profile approaches the ones expected for thermal states already for very small perturbations. On the other hand, other scar signatures, such as the revivals of states having large overlap with scars, show remarkable robustness. Additionally, we examined the effects of minor disturbances on initial states that previously exhibited high overlap with scars and consistent revivals. Our analysis revealed that different types of disturbances can induce markedly different behaviors, such as partially "freezing" the chain, leading to sustained oscillations, or accelerating the process of thermalization.
Related papers
- Experimental protocol for observing single quantum many-body scars with transmon qubits [0.0]
Single quantum many-body scars are energy eigenstates which fail to reproduce thermal expectation values of local observables.
Here we propose protocols to observe single scars in architectures of fixed-frequency, fixed-coupling superconducting qubits.
arXiv Detail & Related papers (2024-10-18T17:11:11Z) - Layer-Aware Analysis of Catastrophic Overfitting: Revealing the Pseudo-Robust Shortcut Dependency [61.394997313144394]
Catastrophic overfitting (CO) presents a significant challenge in single-step adversarial training (AT)
We show that during CO, the former layers are more susceptible, experiencing earlier and greater distortion, while the latter layers show relative insensitivity.
Our proposed method, Layer-Aware Adversarial Weight Perturbation (LAP), can effectively prevent CO and further enhance robustness.
arXiv Detail & Related papers (2024-05-25T14:56:30Z) - Extreme Miscalibration and the Illusion of Adversarial Robustness [66.29268991629085]
Adversarial Training is often used to increase model robustness.
We show that this observed gain in robustness is an illusion of robustness (IOR)
We urge the NLP community to incorporate test-time temperature scaling into their robustness evaluations.
arXiv Detail & Related papers (2024-02-27T13:49:12Z) - Stability of the many-body scars in fermionic spin-1/2 models [0.0]
We study the stability of the many-body scars in spin-1/2 fermionic systems under the most typical perturbations in relevant materials.
We find that some families of scars are completely insensitive to certain perturbations.
In small systems and at small perturbations, we identify and describe an additional stability exhibited by the many-body scars.
arXiv Detail & Related papers (2023-05-26T18:00:03Z) - Tower of quantum scars in a partially many-body localized system [0.0]
We show how one can find disordered Hamiltonians hosting a tower of scars by adapting a known method for finding parent Hamiltonians.
We demonstrate that localization stabilizes scar revivals of initial states with support both inside and outside the scar subspace.
arXiv Detail & Related papers (2023-01-04T16:10:24Z) - Quantum local random networks and the statistical robustness of quantum
scars [68.8204255655161]
We investigate the emergence of quantum scars in a general ensemble of random Hamiltonians.
We find a class of scars, that we call "statistical"
We study the scaling of the number of statistical scars with system size.
arXiv Detail & Related papers (2021-07-02T07:53:09Z) - Deconfounded Score Method: Scoring DAGs with Dense Unobserved
Confounding [101.35070661471124]
We show that unobserved confounding leaves a characteristic footprint in the observed data distribution that allows for disentangling spurious and causal effects.
We propose an adjusted score-based causal discovery algorithm that may be implemented with general-purpose solvers and scales to high-dimensional problems.
arXiv Detail & Related papers (2021-03-28T11:07:59Z) - Exact many-body scars and their stability in constrained quantum chains [55.41644538483948]
Quantum scars are non-thermal eigenstates characterized by low entanglement entropy.
We study the response of these exact quantum scars to perturbations by analysing the scaling of the fidelity susceptibility with system size.
arXiv Detail & Related papers (2020-11-16T19:05:50Z) - Enhancing the effect of quantum many-body scars on dynamics by
minimising the effective dimension [0.0]
Quantum many-body scarring is believed to be the mechanism behind long-lived coherent oscillations in interacting Rydberg atom chains.
These persistent oscillations are due to the large overlap of the many-body scars with certain initial states.
We show that the "effective dimension" is a useful measure for identifying non-thermalising initial states in many-body scarred systems.
arXiv Detail & Related papers (2020-06-04T18:54:14Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.