Entanglement generation and scaling from noisy quenches across a quantum critical point
- URL: http://arxiv.org/abs/2503.03584v1
- Date: Wed, 05 Mar 2025 15:19:23 GMT
- Title: Entanglement generation and scaling from noisy quenches across a quantum critical point
- Authors: R. Jafari, J. Naji, A. Langari, Vahid Karimipour, Henrik Johannesson,
- Abstract summary: We study the impact of noise on the dynamics of entanglement in the transverse-field Ising chain.<n>We find that a quench generates entanglement between nearest- and next-nearest-neighbor spins, with noise reducing the amount of entanglement.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We study the impact of noise on the dynamics of entanglement in the transverse-field Ising chain, with the field quenched linearly across one or both of the quantum critical points of the model. Taking concurrence as a measure of entanglement, we find that a quench generates entanglement between nearest- and next-nearest-neighbor spins, with noise reducing the amount of entanglement. Focusing on the next-nearest-neighbor concurrence, known to exhibit Kibble-Zurek scaling with the square root of the quench rate in the noiseless case, we find a different result when noise is present: The concurrence now scales logarithmically with the quench rate, with a noise-dependent amplitude. This is also different from the ``anti-Kibble-Zurek" scaling of defect density with quench rate when noise is present, suggesting that noisy entanglement generation is largely independent from the rate of defect formation. Intriguingly, the critical time scale beyond which no entanglement is produced by a noisy quench scales as a power law with the strength of noise, with the same exponent as that which governs the optimal quench time for which defect formation is at a minimum in a standard quantum annealing scheme.
Related papers
- Anti Kibble-Zurek behavior in the quantum XY spin-1/2 chain driven by correlated noisy magnetic field and anisotropy [0.0]
In the non-adiabatic dynamics across a quantum phase transition, the Kibble-Zurek paradigm describes that the average number of topological defects is suppressed as a universal power law with the quench time scale.<n>Here, we study the defect generation in the driven transverse field/anisotropy quantum $XY$ model in the presence of a correlated (colored) noise.
arXiv Detail & Related papers (2025-03-05T11:35:49Z) - Mixed-State Topological Order under Coherent Noises [2.8391355909797644]
We find remarkable stability of mixed-state topological order under random rotation noise with axes near the $Y$-axis of qubits.
The upper bounds for the intrinsic error threshold are determined by these phase boundaries, beyond which quantum error correction becomes impossible.
arXiv Detail & Related papers (2024-11-05T19:00:06Z) - Characterizing Noise of Driven Controlled Field Using the Central Spin Model [0.0]
We analyze the coherence dynamics of a central spin coupled to a spin chain with a time-dependent noisy magnetic field.
Our results show that decoherency due to the nonequilibrium critical dynamics of the environment is amplified in the presence of uncorrelated and correlated noise.
Our findings have potential applications in the noise spectroscopy of external signals.
arXiv Detail & Related papers (2024-09-02T17:12:00Z) - Stochastic action for the entanglement of a noisy monitored two-qubit
system [55.2480439325792]
We study the effect of local unitary noise on the entanglement evolution of a two-qubit system subject to local monitoring and inter-qubit coupling.
We construct a Hamiltonian by incorporating the noise into the Chantasri-Dressel-Jordan path integral and use it to identify the optimal entanglement dynamics.
Numerical investigation of long-time steady-state entanglement reveals a non-monotonic relationship between concurrence and noise strength.
arXiv Detail & Related papers (2024-03-13T11:14:10Z) - Characterizing low-frequency qubit noise [55.41644538483948]
Fluctuations of the qubit frequencies are one of the major problems to overcome on the way to scalable quantum computers.
The statistics of the fluctuations can be characterized by measuring the correlators of the outcomes of periodically repeated Ramsey measurements.
This work suggests a method that allows describing qubit dynamics during repeated measurements in the presence of evolving noise.
arXiv Detail & Related papers (2022-07-04T22:48:43Z) - Stabilizing and improving qubit coherence by engineering noise spectrum
of two-level systems [52.77024349608834]
Superconducting circuits are a leading platform for quantum computing.
Charge fluctuators inside amorphous oxide layers contribute to both low-frequency $1/f$ charge noise and high-frequency dielectric loss.
We propose to mitigate those harmful effects by engineering the relevant TLS noise spectral densities.
arXiv Detail & Related papers (2022-06-21T18:37:38Z) - High-Order Qubit Dephasing at Sweet Spots by Non-Gaussian Fluctuators:
Symmetry Breaking and Floquet Protection [55.41644538483948]
We study the qubit dephasing caused by the non-Gaussian fluctuators.
We predict a symmetry-breaking effect that is unique to the non-Gaussian noise.
arXiv Detail & Related papers (2022-06-06T18:02:38Z) - Learning Noise via Dynamical Decoupling of Entangled Qubits [49.38020717064383]
Noise in entangled quantum systems is difficult to characterize due to many-body effects involving multiple degrees of freedom.
We develop and apply multi-qubit dynamical decoupling sequences that characterize noise that occurs during two-qubit gates.
arXiv Detail & Related papers (2022-01-26T20:22:38Z) - Dynamics of discrete-time quantum walk with time-correlated unitary
noise [0.0]
We investigate the dynamics of discrete-time quantum walk subject to time correlated noise.
Two remarker behaviors of long time noisy dynamics are observed in numerical simulations.
In fast noise regime, the walker is confined into few lattice sites, and the width of wave packet is much narrower compared with that in slow noise regime.
arXiv Detail & Related papers (2020-11-20T10:23:46Z) - Shape Matters: Understanding the Implicit Bias of the Noise Covariance [76.54300276636982]
Noise in gradient descent provides a crucial implicit regularization effect for training over parameterized models.
We show that parameter-dependent noise -- induced by mini-batches or label perturbation -- is far more effective than Gaussian noise.
Our analysis reveals that parameter-dependent noise introduces a bias towards local minima with smaller noise variance, whereas spherical Gaussian noise does not.
arXiv Detail & Related papers (2020-06-15T18:31:02Z)
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.