Quantum-classical crossover in noisy monitored oscillators

• URL: http://arxiv.org/abs/2608.08267v1
• Date: Sat, 08 Aug 2026 17:57:15 GMT
• Title: Quantum-classical crossover in noisy monitored oscillators
• Abstract summary: We find that projective measurements and energy quantization lead to substantial differences between the quantum and classical first-passage-time distributions.<n>Individual trajectories reveal emergent quantum signatures from the repeated measurements, such as persistent Wigner negativity.<n>Our results provide a framework for using first-passage processes to create measurement-induced nonclassical resource states.
• Score: 0.06363400715351396
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The quantum first-passage problem involves stochastic trajectories conditioned on measurement outcomes. The timing statistics of such trajectories remain largely unexplored in open quantum systems. Here, we investigate the first-passage time to an energy threshold for a ubiquitous model: a harmonic oscillator driven by classical additive noise. We find that projective measurements and energy quantization lead to substantial differences between the quantum and classical first-passage-time distributions at low thresholds, while these differences gradually diminish as the threshold energy increases. We treat the problem using both ensemble-averaged conditioned density-matrix dynamics and trajectory-resolved stochastic pure-state dynamics. The two descriptions yield indistinguishable timing statistics. Quantization effects appear in the ensemble-level phase-space distributions of the surviving states and vanish at larger threshold energies. Individual trajectories reveal emergent quantum signatures from the repeated measurements, such as persistent Wigner negativity. Our results provide a framework for using first-passage processes to create measurement-induced nonclassical resource states and to study the quantum-classical crossover of monitored systems.

Related papers

• Generation of entanglement and magic via continuous homodyne monitoring of a qubit pair [0.0]
  Continuous weak measurements of quantum systems are of great relevance in quantum foundations and applications.<n>We study two qubits coupled in different points to a common one-dimensional electromagnetic field and simultaneously monitored by homodyne detection.<n>We show that continuous monitoring generates entanglement, absent in the unconditional dynamics, and enhances quantum magic in the qubit pair during the decay.
  arXiv  Detail & Related papers  (2026-09-14T16:57:56Z)
• Universal classical and quantum fluctuations in the large deviations of current of noisy quantum systems: The case of QSSEP and QSSIP [2.035631599424874]
  We study the fluctuation statistics of integrated currents in noisy quantum diffusive systems.<n>We show that the cumulant generating function of the integrated current, at large scales, obeys a large deviation principle.<n>We identify the leading finite-size corrections to the current statistics.
  arXiv  Detail & Related papers  (2026-01-23T16:45:31Z)
• Classical and quantum chaotic synchronization in coupled dissipative time crystals [0.0]
  We study the dynamics of two coherently coupled dissipative time crystals.<n>In analogy with the classical case, we interpret this behavior as quantum chaotic synchronization.
  arXiv  Detail & Related papers  (2025-09-25T09:03:58Z)
• Magnetic Memory and Hysteresis from Quantum Transitions: Theory and Experiments on Quantum Annealers [0.6990493129893112]
  We present a conceptual framework that explains the observed behavior by combining two-level-Zener transitions via a first-order piecewise- propagator with semiclassical domain-wall kinetics.<n>Our framework reproduces the measured densities, loops, shapes, and longitudinal sweep-rate scaling trends observed data from three different D-Wave annealers.<n>These results establish programmable quantum annealers as powerful testbeds for exploring memory-endowed non-equilibrium dynamics in quantumbody systems.
  arXiv  Detail & Related papers  (2025-07-24T04:03:04Z)
• Work Statistics and Quantum Trajectories: No-Click Limit and non-Hermitian Hamiltonians [50.24983453990065]
  We present a framework for quantum work statistics in continuously monitored quantum systems.<n>Our approach naturally incorporates non-Hermitian dynamics arising from quantum jump processes.<n>We illustrate our theoretical framework by analyzing a one-dimensional transverse-field Ising model under local spin monitoring.
  arXiv  Detail & Related papers  (2025-04-15T23:21:58Z)
• 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)
• Quantifying measurement-induced quantum-to-classical crossover using an open-system entanglement measure [49.1574468325115]
  We study the entanglement of a single particle under continuous measurements. We find that the entanglement at intermediate time scales shows the same qualitative behavior as a function of the measurement strength.
  arXiv  Detail & Related papers  (2023-04-06T09:45:11Z)
• Evolution of many-body systems under ancilla quantum measurements [58.720142291102135]
  We study the concept of implementing quantum measurements by coupling a many-body lattice system to an ancillary degree of freedom. We find evidence of a disentangling-entangling measurement-induced transition as was previously observed in more abstract models.
  arXiv  Detail & Related papers  (2023-03-13T13:06:40Z)
• 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)
• Classical and statistical limits of the quantum singular oscillator [0.0]
  Weyl-Wigner phase-space and Bohmian mechanics frameworks are used. Two inequivalent quantum systems are shown to be statistically equivalent at thermal equilibrium.
  arXiv  Detail & Related papers  (2020-07-10T19:07:33Z)
• Quantum Zeno effect appears in stages [64.41511459132334]
  In the quantum Zeno effect, quantum measurements can block the coherent oscillation of a two level system by freezing its state to one of the measurement eigenstates. We show that the onset of the Zeno regime is marked by a $textitcascade of transitions$ in the system dynamics as the measurement strength is increased.
  arXiv  Detail & Related papers  (2020-03-23T18:17:36Z)

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.