Fundamental Costs of Noise-Robust Quantum Control: Speed Limits and Complexity
- URL: http://arxiv.org/abs/2510.07183v1
- Date: Wed, 08 Oct 2025 16:21:33 GMT
- Title: Fundamental Costs of Noise-Robust Quantum Control: Speed Limits and Complexity
- Abstract summary: Noise is ubiquitous in quantum systems and is a major obstacle for the advancement of quantum information science.<n>Noise-robust quantum control achieves high-fidelity operations by engineering the evolution path so that first-order noise contributions cancel at the final time.<n>We derive general lower bounds on control complexity that quantify this overhead for quasi-static coherent noise under bounded control amplitude.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Noise is ubiquitous in quantum systems and is a major obstacle for the advancement of quantum information science. Noise-robust quantum control achieves high-fidelity operations by engineering the evolution path so that first-order noise contributions cancel at the final time. Such dynamical error correction typically incurs a time overhead beyond standard quantum speed limits. We derive general lower bounds on control complexity that quantify this overhead for quasi-static coherent noise under bounded control amplitude. For a single noise source, we prove a universal time lower bound for first-order robustness and give a constructive scheme that implements any target gate robustly in time 4T plus a constant time. For robustness against an entire noise space, we show dimension lower bounds on the number M of segments in any mixed-unitary schedule from two mechanism: (i) a coherent dimension bound when the error subspace contains an irreducible block isomorphic to su(q), and (ii) a projection dimension bound when the noise space contains the trace-zero span of orthogonal projectors. Under bounded speed, these bounds on number of segments imply time lower bounds. With only local controls robust against noise space defined on a graph, we obtain a graph-orthogonality time bound scales linear with graph chromatic number. We illustrate the bounds through examples. Collectively, these results establish quantitative limitations on the feasibility of first-order noise-resilient operations.
Related papers
- Coherent-disorder-driven complexity transitions in a quantum-advantage architecture [0.15554979526414522]
We study a square-lattice instantaneous quantum-time architecture subject to two-qubit gate-angle disorder and single-qubit dephasing.<n>For finite systems without dephasing, increasing disorder drives two consecutive crossovers toward classical simulability.
arXiv Detail & Related papers (2026-07-21T10:21:24Z) - Quantum Magnetometry with Orientation beyond Steady-State Limits in Cavity-Magnon Systems [3.7474502478967238]
We present a transient quantum sensing framework for cavity-magnon systems.<n>We show that residual initial quantum correlations can drastically enhance the short-time signal-to-noise ratio.<n>Our results establish a unified route to scalable, high precision, multidimensional quantum magnetometry.
arXiv Detail & Related papers (2026-04-30T09:00:03Z) - Precision bounds for frequency estimation under collective dephasing and open-loop control [0.0]
We address the problem of entanglement-assisted frequency estimation subject to classical dephasing noise.<n>We derive rigorous, state-independent bounds on the achievable estimation precision.<n>We prove that arbitrary collective open-loop control cannot lift the no-go for super-classical precision scaling under either Markovian or colored stationary noise.
arXiv Detail & Related papers (2026-03-25T00:26:14Z) - Instantaneous Sobolev Regularization for Dissipative Bosonic Dynamics [1.7205106391379026]
We investigate quantum Markov semigroups on bosonic Fock space.<n>We identify a broad class of infinite-dimensional dissipative evolutions that exhibit Sobolev-regularization.
arXiv Detail & Related papers (2025-12-03T18:48:55Z) - Fault-tolerant quantum computation with constant overhead for general noise [8.49301882142233]
We show that fault-tolerant quantum computation can be achieved with constant qubit overhead under general noise models.<n>We develop a fault-tolerant error correction scheme and a method for implementing logic gates under general circuit noise.
arXiv Detail & Related papers (2025-12-02T13:41:25Z) - Second-order Optimization under Heavy-Tailed Noise: Hessian Clipping and Sample Complexity Limits [53.773695219320125]
We take a first step toward a theoretical understanding of second-order optimization under heavy-tailed noise.<n>We introduce a novel algorithm based on gradient and Hessian clipping, and prove high-probability upper bounds that nearly match the fundamental limits.
arXiv Detail & Related papers (2025-10-12T16:36:54Z) - Quartic quantum speedups for community detection [84.14713515477784]
We develop a quantum algorithm for hypergraph community detection that achieves a quartic quantum speedup.<n>Our algorithm is based on the Kikuchi method, which we extend beyond previously considered problems such as PCA and $p$XORSAT.
arXiv Detail & Related papers (2025-10-09T17:35:17Z) - A unified relativistic path integral origin for noise-activated collapse and decoherence [6.864380740265179]
We construct a relativistic path integral that recovers the Dirac, Klein-Gordon, and Schr"odinger equations.<n>This term dormant in differentiable potentials but is activated by non-differentiable noise, driving outcome probabilities through bounded-martingale process.<n>Because the trigger is the noise spectrum, our work shows that engineering colored'' noise can expedite or steer collapse.
arXiv Detail & Related papers (2025-09-20T01:58:50Z) - Time-dependent Neural Galerkin Method for Quantum Dynamics [42.81677042059531]
We introduce a classical computational method for quantum dynamics that relies on a global-in-time variational principle.<n>Our scheme computes the entire state trajectory over a finite time window by minimizing a loss function that enforces the Schr"odinger's equation.<n>We showcase the method by simulating global quantum quenches in the paradigmatic Transverse-Field Ising model in both 1D and 2D.
arXiv Detail & Related papers (2024-12-16T13:48:54Z) - 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) - Clustered Switchback Designs for Experimentation Under Spatio-temporal Interference [44.644520116360106]
We estimate the global average treatment effect (GATE), the difference between average outcomes having exposed all units at all times to treatment or to control.<n>We propose a clustered switchback design, where units are grouped into clusters and time steps are grouped into blocks.<n>We show that for graphs that admit good clustering, a truncated Horvitz-Thompson estimator achieves a $tilde O(1/NT)$ mean squared error (MSE)<n>Our results simultaneously generalize the results from citethu2022switchback,ugander2013graph and citetleung2022rate
arXiv Detail & Related papers (2023-12-25T01:00:58Z) - Chaotic fluctuations in a universal set of transmon qubit gates [37.69303106863453]
Transmon qubits arise from the quantization of nonlinear resonators.
Fast entangling gates, operating at speeds close to the so-called quantum speed limit, contain transient regimes where the dynamics indeed becomes partially chaotic for just two transmons.
arXiv Detail & Related papers (2023-11-24T16:30:56Z) - Quantum Speed Limit for Change of Basis [55.500409696028626]
We extend the notion of quantum speed limits to collections of quantum states.
For two-qubit systems, we show that the fastest transformation implements two Hadamards and a swap of the qubits simultaneously.
For qutrit systems the evolution time depends on the particular type of the unbiased basis.
arXiv Detail & Related papers (2022-12-23T14:10:13Z) - Quantum Worst-Case to Average-Case Reductions for All Linear Problems [66.65497337069792]
We study the problem of designing worst-case to average-case reductions for quantum algorithms.
We provide an explicit and efficient transformation of quantum algorithms that are only correct on a small fraction of their inputs into ones that are correct on all inputs.
arXiv Detail & Related papers (2022-12-06T22:01:49Z) - A Converse for Fault-tolerant Quantum Computation [1.2031796234206134]
In this paper, we obtain a lower bound on the redundancy required for $epsilon$-accurate implementation of a class of operations that includes unitary operators.
For the practically relevant case of sub-exponential depth and sub-linear gate size, our bound on redundancy is tighter than the known lower bounds.
arXiv Detail & Related papers (2022-11-01T18:43:14Z) - Multi-squeezed state generation and universal bosonic control via a
driven quantum Rabi model [68.8204255655161]
Universal control over a bosonic degree of freedom is key in the quest for quantum-based technologies.
Here we consider a single ancillary two-level system, interacting with the bosonic mode of interest via a driven quantum Rabi model.
We show that it is sufficient to induce the deterministic realization of a large class of Gaussian and non-Gaussian gates, which in turn provide universal bosonic control.
arXiv Detail & Related papers (2022-09-16T14:18:53Z) - Learning Noise via Dynamical Decoupling of Entangled Qubits [49.38020717064383]
Noise in entangled quantum systems is difficult to characterize due to many-body effects involving multiple degrees of freedom.
We develop and apply multi-qubit dynamical decoupling sequences that characterize noise that occurs during two-qubit gates.
arXiv Detail & Related papers (2022-01-26T20:22:38Z) - Designing arbitrary single-axis rotations robust against perpendicular
time-dependent noise [0.0]
We introduce a protocol to design bounded and continuous control fields that implement arbitrary single-axis rotations.
We show the versatility of our method by presenting a set of non-negative-only control pulses.
arXiv Detail & Related papers (2021-03-15T16:26:57Z)
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.