State Diagnostics of Complexity in Open Quantum Systems

• URL: http://arxiv.org/abs/2608.09705v1
• Date: Mon, 10 Aug 2026 15:09:52 GMT
• Title: State Diagnostics of Complexity in Open Quantum Systems
• Abstract summary: We study the emergence of complexity in finite-size quantum systems.<n>We represent mixed quantum states as probability measures on complex projective Hilbert space.
• Score: 39.146761527401424
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We study the emergence of complexity in finite-size quantum systems as their dynamics transition from closed and coherent evolution to interacting and effectively open behavior. Using a state-based geometric framework, we represent mixed quantum states as probability measures on complex projective Hilbert space. This representation allows us to track how interactions reshape the underlying pure-state geometry. We introduce two complementary diagnostics: a distinguishability measure, based on the Wasserstein distance between probability-measure representations of mixed states, that quantifies sensitivity to initial states, and a state-space coverage index that measures long-time exploration of the subsystem state space. These diagnostics provide a geometric perspective on the emergence and evolution of quantum dynamical complexity. When applied to the quantum kicked top, both diagnostics generally increase with interaction strength. Their dependence on environment size is structured by parity symmetry, with integer-spin systems often exhibiting greater sensitivity and state-space coverage than half-integer-spin systems. These results highlight finite-size quantum effects and provide a geometric approach to quantifying dynamical complexity deep in the quantum regime

Related papers

• Statistical and Algorithmic Foundations of Probing Quantum Systems with Compressive Measurements: A Review [23.123362765639214]
  Quantum state tomography aims to reconstruct unknown quantum states from measurement data.<n>Prior structure, such as low-rankness, tensor-network representations, shallow quantum circuits, and neural quantum states, can substantially reduce the effective degrees of freedom.
  arXiv  Detail & Related papers  (2026-05-26T15:44:42Z)
• Phase-space complexity of discrete-variable quantum states and operations [0.0]
  We introduce a quantifier of phase-space complexity for discrete-variable quantum systems.<n>The complexity is normalized such that coherent states have unit complexity, while the completely mixed state has zero complexity.<n>We extend the framework to quantum channels, defining measures for both the generation and breaking of complexity.
  arXiv  Detail & Related papers  (2026-03-03T19:00:02Z)
• Geometry and quantum brachistochrone analysis of multiple entangled spin-1/2 particles under all-range Ising interaction [0.0]
  We present a unified geometric and dynamical framework for a physical system consisting of $n$ spin-$1/2$ particles with all-range Ising interaction.<n>Our analysis reveals that the system evolves over a smooth, compact, two-dimensional manifold with spherical topology.<n>We explore the role of entanglement in shaping the state space geometry, modulating geometric phase, and controlling evolution speed and brachistochrone time.
  arXiv  Detail & Related papers  (2025-12-24T19:37:07Z)
• Solving excited states for long-range interacting trapped ions with neural networks [4.294084794573824]
  We introduce a neural network-based algorithm that simultaneously output multiple low-lying excited states of a quantum many-body spin system.<n>The NQES algorithm is capable of efficiently computing multiple excited states and their related observable expectations.<n>Our results establish a scalable and efficient algorithm for computing excited states of interacting quantum many-body systems.
  arXiv  Detail & Related papers  (2025-06-10T09:02:59Z)
• Effect of the readout efficiency of quantum measurement on the system entanglement [44.99833362998488]
  We quantify the entanglement for a particle on a 1d quantum random walk under inefficient monitoring. We find that the system's maximal mean entanglement at the measurement-induced quantum-to-classical crossover is in different ways by the measurement strength and inefficiency.
  arXiv  Detail & Related papers  (2024-02-29T18:10:05Z)
• Enhanced Entanglement in the Measurement-Altered Quantum Ising Chain [43.80709028066351]
  Local quantum measurements do not simply disentangle degrees of freedom, but may actually strengthen the entanglement in the system.<n>This paper explores how a finite density of local measurement modifies a given state's entanglement structure.
  arXiv  Detail & Related papers  (2023-10-04T09:51:00Z)
• Neural-Network Quantum States for Periodic Systems in Continuous Space [66.03977113919439]
  We introduce a family of neural quantum states for the simulation of strongly interacting systems in the presence of periodicity. For one-dimensional systems we find very precise estimations of the ground-state energies and the radial distribution functions of the particles. In two dimensions we obtain good estimations of the ground-state energies, comparable to results obtained from more conventional methods.
  arXiv  Detail & Related papers  (2021-12-22T15:27:30Z)
• Sensing quantum chaos through the non-unitary geometric phase [62.997667081978825]
  We propose a decoherent mechanism for sensing quantum chaos. The chaotic nature of a many-body quantum system is sensed by studying the implications that the system produces in the long-time dynamics of a probe coupled to it.
  arXiv  Detail & Related papers  (2021-04-13T17:24:08Z)
• Multidimensional dark space and its underlying symmetries: towards dissipation-protected qubits [62.997667081978825]
  We show that a controlled interaction with the environment may help to create a state, dubbed as em dark'', which is immune to decoherence. To encode quantum information in the dark states, they need to span a space with a dimensionality larger than one, so different states act as a computational basis. This approach offers new possibilities for storing, protecting and manipulating quantum information in open systems.
  arXiv  Detail & Related papers  (2020-02-01T15:57:37Z)

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.