Bridging Classical and Quantum Information Scrambling with the Operator Entanglement Spectrum
- URL: http://arxiv.org/abs/2505.05575v2
- Date: Mon, 12 May 2025 17:56:49 GMT
- Title: Bridging Classical and Quantum Information Scrambling with the Operator Entanglement Spectrum
- Authors: Ben T. McDonough, Claudio Chamon, Justin H. Wilson, Thomas Iadecola,
- Abstract summary: We show that differences between automaton dynamics and fully quantum dynamics are revealed by the operator entanglement spectrum.<n>We find that a constant number of superposition-generating gates is sufficient to drive the operator dynamics to the random-circuit class.<n>This establishes the operator entanglement spectrum as a useful tool for probing the chaoticity and universality class of quantum dynamics.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Universal features of chaotic quantum dynamics underlie our understanding of thermalization in closed quantum systems and the complexity of quantum computations. Reversible automaton circuits, comprised of classical logic gates, have emerged as a tractable means to study such dynamics. Despite generating no entanglement in the computational basis, these circuits nevertheless capture many features expected from fully quantum evolutions. In this work, we demonstrate that the differences between automaton dynamics and fully quantum dynamics are revealed by the operator entanglement spectrum, much like the entanglement spectrum of a quantum state distinguishes between the dynamics of states under Clifford and Haar random circuits. While the operator entanglement spectrum under random unitary dynamics is governed by the eigenvalue statistics of random Gaussian matrices, we show evidence that under random automaton dynamics it is described by the statistics of Bernoulli random matrices, whose entries are random variables taking values $0$ or $1$. We study the crossover between automaton and generic unitary operator dynamics as the automaton circuit is doped with gates that introduce superpositions, namely Hadamard or $R_x = e^{-i\frac{\pi}{4}X}$ gates. We find that a constant number of superposition-generating gates is sufficient to drive the operator dynamics to the random-circuit universality class, similar to earlier results on Clifford circuits doped with $T$ gates. This establishes the operator entanglement spectrum as a useful tool for probing the chaoticity and universality class of quantum dynamics.
Related papers
- Constructive interference at the edge of quantum ergodic dynamics [116.94795372054381]
We characterize ergodic dynamics using the second-order out-of-time-order correlators, OTOC$(2)$.<n>In contrast to dynamics without time reversal, OTOC$(2)$ are observed to remain sensitive to the underlying dynamics at long time scales.
arXiv Detail & Related papers (2025-06-11T21:29:23Z) - Characterizing randomness in parameterized quantum circuits through expressibility and average entanglement [39.58317527488534]
Quantum Circuits (PQCs) are still not fully understood outside the scope of their principal application.<n>We analyse the generation of random states in PQCs under restrictions on the qubits connectivities.<n>We place a connection between how steep is the increase on the uniformity of the distribution of the generated states and the generation of entanglement.
arXiv Detail & Related papers (2024-05-03T17:32:55Z) - Hysteresis and Self-Oscillations in an Artificial Memristive Quantum Neuron [79.16635054977068]
We study an artificial neuron circuit containing a quantum memristor in the presence of relaxation and dephasing.
We demonstrate that this physical principle enables hysteretic behavior of the current-voltage characteristics of the quantum device.
arXiv Detail & Related papers (2024-05-01T16:47:23Z) - Quantum fluctuation dynamics of open quantum systems with collective
operator-valued rates, and applications to Hopfield-like networks [0.0]
We consider a class of open quantum many-body systems that evolves in a Markovian fashion, the dynamical generator being in GKS-Lindblad form.
Focusing on the dynamics emerging in the limit of infinitely large systems, we build on the exactness of the mean-field equations for the dynamics of average operators.
In this framework, we derive the dynamics of quantum fluctuation operators, that can be used in turn to understand the fate of quantum correlations in the system.
arXiv Detail & Related papers (2024-02-01T17:23:32Z) - Universality of critical dynamics with finite entanglement [68.8204255655161]
We study how low-energy dynamics of quantum systems near criticality are modified by finite entanglement.
Our result establishes the precise role played by entanglement in time-dependent critical phenomena.
arXiv Detail & Related papers (2023-01-23T19:23:54Z) - Noisy Quantum Kernel Machines [58.09028887465797]
An emerging class of quantum learning machines is that based on the paradigm of quantum kernels.
We study how dissipation and decoherence affect their performance.
We show that decoherence and dissipation can be seen as an implicit regularization for the quantum kernel machines.
arXiv Detail & Related papers (2022-04-26T09:52:02Z) - Effective field theory of random quantum circuits [0.0]
This work develops an effective field theory for a large class of random quantum circuits.
The method is used to explicitly derive universal random matrix behavior of a large family of random circuits.
arXiv Detail & Related papers (2022-04-06T21:03:46Z) - Quantum simulation of $\phi^4$ theories in qudit systems [53.122045119395594]
We discuss the implementation of quantum algorithms for lattice $Phi4$ theory on circuit quantum electrodynamics (cQED) system.
The main advantage of qudit systems is that its multi-level characteristic allows the field interaction to be implemented only with diagonal single-qudit gates.
arXiv Detail & Related papers (2021-08-30T16:30:33Z) - Subdiffusion and many-body quantum chaos with kinetic constraints [0.0]
We find universality classes with diffusive, subdiffusive, quasilocalized, and localized dynamics.
In particular, we show that quantum systems with 'Fredkin constraints' exhibit anomalous transport with dynamical exponent $z simeq 8/3$.
arXiv Detail & Related papers (2021-08-04T18:00:00Z) - Information Scrambling in Computationally Complex Quantum Circuits [56.22772134614514]
We experimentally investigate the dynamics of quantum scrambling on a 53-qubit quantum processor.
We show that while operator spreading is captured by an efficient classical model, operator entanglement requires exponentially scaled computational resources to simulate.
arXiv Detail & Related papers (2021-01-21T22:18:49Z) - Chaos and Ergodicity in Extended Quantum Systems with Noisy Driving [0.0]
We study the time evolution operator in a family of local quantum circuits with random fields in a fixed direction.
We show that for the systems under consideration the generalised spectral form factor can be expressed in terms of dynamical correlation functions.
This also provides a connection between the many-body Thouless time $tau_rm th$ -- the time at which the generalised spectral form factor starts following the random matrix theory prediction -- and the conservation laws of the system.
arXiv Detail & Related papers (2020-10-23T15:54:55Z) - Quantum State Complexity in Computationally Tractable Quantum Circuits [0.0]
We discuss a special class of numerically tractable quantum circuits, known as quantum automaton circuits.
We show that automaton wave functions have high quantum state complexity.
We present evidence of a linear growth of design complexity in local quantum circuits.
arXiv Detail & Related papers (2020-09-11T16:25:11Z)
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.