Related papers: Qubit dynamics with classical noise

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Pseudoentanglement in constant depth: How trivial states can have non-trivial entanglement structure [52.51019642214249]
We construct a family of 2D-local constant-depth quantum circuits whose entanglement entropy across a cut cannot be estimated in quantum time.<n>As constant-depth quantum circuits can be learned from specifiedly many quantum samples, our resulting pseudoentangled states are implicitly public-key and not pseudorandom.
arXiv Detail & Related papers (2026-05-29T15:43:00Z)
Comment on: "Scaling and Universality at Noisy Quench Dynamical Quantum Phase Transitions" [0.0]
In this comment we rigorously prove that in any two-dimensional Hilbert space the Loschmidt echo of two density matrices can only become zero if and only if both density matrices are pure.<n>The existence of DQPTs in the considered scenario is strictly ruled out for non-zero noise because the considered averaging leads to a mixed state.
arXiv Detail & Related papers (2025-11-20T16:27:19Z)
Limitations of Noisy Geometrically Local Quantum Circuits [0.2039123720459736]
We show that noisy quantum circuits with interspersed noise converge to the uniform distribution at $omega(log n)$ depth, where $n$ is the number of qubits.<n>We conjecture that our bound is still loose and that a $Theta(1)$-depth threshold suffices for simulability due to a percolation effect.
arXiv Detail & Related papers (2025-10-07T18:08:23Z)
Noise-Affected Dynamical Quantum Phase Transitions [0.0]
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In variational quantum algorithms the parameters of a parameterized quantum circuit are optimized in order to minimize a cost function that encodes the solution of the problem. We discuss how, and in which sense, the phenomenon of noise-induced barren plateaus emerges in parameterized quantum circuits with a layered noise model.
arXiv Detail & Related papers (2023-10-12T15:18:27Z)
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arXiv Detail & Related papers (2023-05-25T11:11:31Z)
Theory of qubit noise characterization using the long-time cavity transmission [0.0]
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Learning Noise via Dynamical Decoupling of Entangled Qubits [49.38020717064383]
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arXiv Detail & Related papers (2021-07-20T18:44:06Z)
Evaluating the noise resilience of variational quantum algorithms [0.0]
We simulate the effects of different types of noise in state preparation circuits of variational quantum algorithms. We find that the inclusion of redundant parameterised gates makes the quantum circuits more resilient to noise.
arXiv Detail & Related papers (2020-11-02T16:56:58Z)

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