Parameter trajectory engineering for state transfer and quantum sensing in non-Hermitian two-level systems

• URL: http://arxiv.org/abs/2603.24032v1
• Date: Wed, 25 Mar 2026 07:47:46 GMT
• Title: Parameter trajectory engineering for state transfer and quantum sensing in non-Hermitian two-level systems
• Abstract summary: We show how trajectory design governs state-transfer symmetry, robustness, and sensing performance.<n>For quantum sensing, trajectory engineering enables tuning of sensitivity amplitude, time window, and parameter selectivity in both eigenvalue-based and eigenstate-based sensors.
• Score: 3.8814423898242407
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Exceptional points (EPs) in non-Hermitian systems give rise to enhanced sensitivity and chiral state transfer, which are important for quantum technologies. Although parameter trajectories encircling EPs can control symmetric and chiral state transfer, their robustness against practical perturbations and their role in quantum sensing remain largely unexplored. Here, we study three time-modulated parameter loops in a non-Hermitian two-level system to show how trajectory design governs state-transfer symmetry, robustness, and sensing performance. Trajectories avoiding the EP support robust symmetric transfer, while those encircling the EP yield chiral transfer governed by the topological winding number, whose robustness depends on the distance to the EP and the encircling direction. For quantum sensing, trajectory engineering enables tuning of sensitivity amplitude, time window, and parameter selectivity in both eigenvalue-based and eigenstate-based sensors. Notably, eigenstate-based sensing achieves full parameter selectivity that is unattainable with eigenvalue-based methods. Our results establish a quantitative connection between trajectory topology and system dynamics, providing a unified framework for robust state-transfer protocols and high-performance quantum sensors.

Related papers

• Tunable Exceptional Points for Quantum Sensing in a Spin--Orbit-Angular-Momentum Coupled BEC [31.056304866140625]
  We investigate a tunable EP sensing platform based on the intrinsic non-Hermitian Bogoliubov dynamics of a Bose-Einstein condensate.<n>We identify multiple EPs and map their trajectories, revealing strong quantum Fisher information enhancement when the EPs are approached from the PT-symmetric stable regime.<n>We show that a spin-density measurement can approach the quantum Fisher information limit, providing an experimentally accessible route to tunable EP-enhanced quantum sensing in Bose-Einstein condensates.
  arXiv  Detail & Related papers  (2026-08-31T17:03:30Z)
• Quantum-enhanced sensing from the interplay of long-range interactions and non-Hermiticity [0.0]
  Long-range (LR) quantum spin systems offer promising advantages for quantum information processing and sensing.<n>Here, we investigate parameter estimation in a long-range XX spin model coupled to a reservoir.<n>We show that, with suitable tuning of the system parameters, both the time and system-size scaling of the QFI are enhanced in the LR regime.
  arXiv  Detail & Related papers  (2026-05-03T14:47:37Z)
• Non-Equilibrium Criticality-Enhanced Quantum Sensing with Superconducting Qubits [26.523015621022488]
  Exploiting quantum features allows for estimating external parameters with precisions well beyond the capacity of classical sensors.<n>Quantum criticality has been identified as a resource for achieving such enhancements with respect to the probe size.<n>Non-equilibrium probes harness dynamics, enabling quantum-enhanced precision with respect to time over a wide range of parameters.
  arXiv  Detail & Related papers  (2025-08-20T04:14:20Z)
• Observation and Modulation of the Quantum Mpemba Effect on a Superconducting Quantum Processor [22.152087534616076]
  In non-equilibrium quantum many-body systems, the quantum Mpemba effect (QME) emerges as a counterintuitive phenomenon.<n>We report the observation and control of QME using a superconducting processor featuring a unique fully connected, tunable-coupling architecture.<n>Our study provides the first demonstration of flexible QME modulation on a superconducting platform with multiple controllable parameters.
  arXiv  Detail & Related papers  (2025-08-11T07:35:26Z)
• Adaptive Bayesian Single-Shot Quantum Sensing [35.355128149649666]
  In variational quantum sensing, a probe quantum system is generated via a parameterized quantum circuit.<n>This paper introduces an adaptive protocol that uses Bayesian inference to optimize the active information gain.
  arXiv  Detail & Related papers  (2025-07-22T11:35:27Z)
• Quantum sensing of displacements with stabilized GKP states [41.94295877935867]
  We show how protocols for the stabilization of Gottesman-Kitaev-Preskill states can be used for the estimation of two-quadrature displacement sensing.<n>Thanks to the stabilization, this sensor is backaction evading and can function continuously without reset, making it well suited for the detection of itinerant signals.
  arXiv  Detail & Related papers  (2025-06-25T17:18:50Z)
• A Two-stage Optimization Method for Wide-range Single-electron Quantum Magnetic Sensing [24.34017006786999]
  Quantum magnetic sensing based on spin systems has emerged as a new paradigm for detecting ultra-weak magnetic fields with unprecedented sensitivity.<n>In this work, we report the design of a new protocol using a two-stage optimization method.<n>The proposed protocol is developed and evaluated in a challenging context of single-shot readout of an NV-center electron spin under a constrained total sensing time budget.
  arXiv  Detail & Related papers  (2025-06-16T13:28:32Z)
• Shortcuts to adiabatic state transfer in time-modulated two-level non-Hermitian systems [0.3926357402982764]
  Non spectral properties of non-Hermitian systems can give rise to intriguing effects that lack counterparts in Hermitian systems. We propose a scheme for achieving robust and rapid adiabatic state transfer in time-modulated two-level non-Hermitian systems.
  arXiv  Detail & Related papers  (2024-11-01T07:52:18Z)
• Restoring Adiabatic State Transfer in Time-Modulated Non-Hermitian Systems [0.0]
  We show that adiabaticity can be achieved when dynamically winding around exceptional points (EPs) in non-Hermitian systems. Our findings offer a promise for advancing various wave manipulation protocols in both quantum and classical domains.
  arXiv  Detail & Related papers  (2024-02-23T12:53:16Z)
• Multiparameter critical quantum metrology with impurity probes [0.0]
  We introduce the two-impurity Kondo (2IK) model as a novel paradigm for critical quantum metrology. We demonstrate that by applying a known control field, the singularity can be removed and measurement sensitivity restored.
  arXiv  Detail & Related papers  (2023-11-28T16:32:51Z)
• Free-Fermionic Topological Quantum Sensors [0.0]
  We analytically demonstrate that quantum enhanced sensing is possible using topological edge states near the phase boundary. While neither symmetry-breaking nor long-range entanglement are essential, gap closing remains as the major candidate for the ultimate source of quantum enhanced sensing.
  arXiv  Detail & Related papers  (2022-01-18T16:27:46Z)

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.