QMaxCal: Path-Space Regularization for Open Quantum Control via Girsanov's Theorem

• URL: http://arxiv.org/abs/2606.19947v1
• Date: Thu, 18 Jun 2026 08:44:18 GMT
• Title: QMaxCal: Path-Space Regularization for Open Quantum Control via Girsanov's Theorem
• Abstract summary: Regularizers are used to drive a system toward states where the effects of decoherence are minimal.<n>Regularizers reduce infidelity by up to 50%, with 16% gains on a calibrated IBM Kingston chain.
• Score: 20.48831221835032
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Reliable quantum control in the presence of decoherence requires policies that combat the effect of environmental noise on the controlled dynamics. Open quantum systems under continuous monitoring generate classical measurement records whose drift depends on the noise experienced by the system; the records of two evolutions sharing the same decoherence channels differ only in this drift, so Girsanov's theorem yields a closed-form, differentiable estimator of the KL divergence between their trajectory distributions. We instantiate this estimator with two physically motivated reference measures, yielding two regularizers that both drive the system toward states where the effects of decoherence are minimal: the Wiener KL (KL_W), which is empirically more effective under certain conditions on the noise model, and the drift-variance regularizer (R_DV), which works for all noise models. Both are qualitatively distinct from existing penalties on control fluence or smoothness: they penalize the observable consequences of control on the decoherence channels rather than the control amplitude itself. The regularizers outperform unregularized gradient-based and reinforcement-learning baselines across a range of open quantum systems -- including single- and multi-qubit benchmarks and a multi-qubit chain calibrated to a published snapshot of the IBM Kingston processor -- along several axes of evaluation: final-state fidelity, robustness to mismatch in the assumed noise model (gains grow from +17 pp at training noise to +27 pp under 2.5x noise mismatch), and occupation of forbidden states. The regularizers reduce infidelity by up to 50%, with ~16% gains on the calibrated IBM Kingston chain.

Related papers

• Noisy quantum circuit simulation with the tensor jump method [4.323508970487569]
  We introduce a variance-aware tensor network framework that combines the tensor jump method with local TDVP gate evolution on matrix product states and sparse Pauli-Lindblad hardware noise models.<n>We demonstrate accurate, scalable noisy-circuit simulation on a 25-qubit noisy XY quench and IBM's 127-qubit kicked-Ising benchmark with long-range depolarizing noise.
  arXiv  Detail & Related papers  (2026-07-01T18:00:01Z)
• The limits of erasure-based postselection for quantum error mitigation [0.0]
  In both classical and quantum error correction, heralded erasures are known to be easier to tolerate than unheralded general errors.<n>This work investigates exploiting these 'erasure qubits' in the near term by using postselection as a technique for error mitigation.
  arXiv  Detail & Related papers  (2026-06-30T09:51:59Z)
• Test-time Adaptive Hierarchical Co-enhanced Denoising Network for Reliable Multimodal Classification [55.56234913868664]
  We propose Test-time Adaptive Hierarchical Co-enhanced Denoising Network (TAHCD) for reliable learning on multimodal data.<n>The proposed method achieves superior classification performance, robustness, and generalization compared with state-of-the-art reliable multimodal learning approaches.
  arXiv  Detail & Related papers  (2026-01-12T03:14:12Z)
• Continual Quantum Architecture Search with Tensor-Train Encoding: Theory and Applications to Signal Processing [68.35481158940401]
  CL-QAS is a continual quantum architecture search framework.<n>It mitigates challenges of costly encoding amplitude and forgetting in variational quantum circuits.<n>It achieves controllable robustness expressivity, sample-efficient generalization, and smooth convergence without barren plateaus.
  arXiv  Detail & Related papers  (2026-01-10T02:36:03Z)
• Universally Robust Control of Open Quantum Systems [0.6086160084025234]
  Mitigating noise-induced decoherence is the central challenge in controlling open quantum systems.<n>We introduce a universal framework for noise-agnostic quantum control that achieves high-fidelity operations without prior environmental noise characterization.
  arXiv  Detail & Related papers  (2025-08-10T15:09:38Z)
• Limitations to Dynamical Error Suppression and Gate-Error Virtualization from Temporally Correlated Nonclassical Noise [0.0]
  We study a minimal exactly solvable single-qubit model under Gaussian quantum dephasing noise.<n>For digital periodic control, we prove that the gate fidelity saturates at a value that is strictly smaller than the one attainable in the absence of control history.<n>We find that only if decoupling can keep the qubit highly pure over a timescale larger than the correlation time of the noise, the bath approximately converges to its original statistics.
  arXiv  Detail & Related papers  (2024-07-05T18:00:00Z)
• Generation of C-NOT, SWAP, and C-Z Gates for Two Qubits Using Coherent and Incoherent Controls and Stochastic Optimization [56.47577824219207]
  We consider a general form of the dynamics of open quantum systems determined by the Gorini-Kossakowsky-Sudarchhan-Lindblad type master equation. We analyze the control problems of generating two-qubit C-NOT, SWAP, and C-Z gates using piecewise constant controls and optimization.
  arXiv  Detail & Related papers  (2023-12-09T17:55:47Z)
• Autonomous coherence protection of a two-level system in a fluctuating environment [68.8204255655161]
  We re-examine a scheme originally intended to remove the effects of static Doppler broadening from an ensemble of non-interacting two-level systems (qubits) We demonstrate that this scheme is far more powerful and can also protect a single (or even an ensemble) qubit's energy levels from noise which depends on both time and space.
  arXiv  Detail & Related papers  (2023-02-08T01:44:30Z)
• Robust Control for Dynamical Systems With Non-Gaussian Noise via Formal Abstractions [59.605246463200736]
  We present a novel controller synthesis method that does not rely on any explicit representation of the noise distributions. First, we abstract the continuous control system into a finite-state model that captures noise by probabilistic transitions between discrete states. We use state-of-the-art verification techniques to provide guarantees on the interval Markov decision process and compute a controller for which these guarantees carry over to the original control system.
  arXiv  Detail & Related papers  (2023-01-04T10:40:30Z)
• Machine Learning assisted excess noise suppression for continuous-variable quantum key distribution [10.533604439090514]
  An excess noise suppression scheme based on equalization is proposed. In this scheme, the distorted signals can be corrected through equalization assisted by a neural network and pilot tone. The experimental results show that the scheme can suppress the excess noise to a lower level, and has a significant performance improvement.
  arXiv  Detail & Related papers  (2022-07-21T12:31:13Z)
• Multipartite entanglement and purity dynamics in classical channels influenced by fractional Gaussian noise [0.5735035463793008]
  We show that indefinite entanglement and purity preservation may be simulated in multipartite GHZ-like states. Different entanglement and mixedness criteria yield different results, emphasizing the need to investigate various approaches in order to uncover multipartite correlations.
  arXiv  Detail & Related papers  (2021-11-03T13:39:57Z)
• Efficient and robust certification of genuine multipartite entanglement in noisy quantum error correction circuits [58.720142291102135]
  We introduce a conditional witnessing technique to certify genuine multipartite entanglement (GME) We prove that the detection of entanglement in a linear number of bipartitions by a number of measurements scales linearly, suffices to certify GME. We apply our method to the noisy readout of stabilizer operators of the distance-three topological color code and its flag-based fault-tolerant version.
  arXiv  Detail & Related papers  (2020-10-06T18:00:07Z)

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.