Achieving the Quantum Limits with Twin-Field Sensors

• URL: http://arxiv.org/abs/2609.07517v1
• Date: Mon, 07 Sep 2026 14:01:25 GMT
• Title: Achieving the Quantum Limits with Twin-Field Sensors
• Abstract summary: Continuous measurements play a fundamental role in quantum experiments.<n>We show that for a wide class of sensors, the quantum Fisher information bound can be saturated through a combined measurement of signals from the original sensor and a suitable system copy.
• Score: 2.644276283063762
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Continuous measurements play a fundamental role in quantum experiments, yet understanding and extracting the maximal possible information in a continuous probe signal remains a significant challenge. In this work, we show that for a wide class of sensors, the quantum Fisher information bound can be saturated through a combined measurement of signals from the original sensor and a suitable system copy. We elucidate the physical mechanism of such a twin-field sensor (TFS) and study its performance across diverse implementations, ranging from two-level atoms to a hybrid quantum Rabi model. In all of these cases, we find that simple photon counting or homodyne detection saturates the theoretical quantum limit. We further prove that the TFS achieves the quantum limits for the joint sensing of pairs of parameters as quantified by the quantum Fisher information matrix.

Related papers

• Quantum-Enhanced Sensing Enabled by Scrambling-Induced Genuine Multipartite Entanglement [20.969785212834793]
  We demonstrate a scrambling-based approach for quantum-enhanced sensing on a superconducting quantum processor.<n>By exploiting many-body information scrambling, we observe quantum-enhanced sensitivity to an encoded phase beyond the standard quantum limit.<n>Our results demonstrate a scalable and practical approach for quantum-enhanced sensing in interacting many-body quantum systems.
  arXiv  Detail & Related papers  (2026-01-30T03:28:36Z)
• Stroboscopic Saturation of Multiparameter Quantum Limits in Distributed Quantum Sensing [0.0]
  High-precision sensors that exploit uniquely quantum phenomena have been shown to surpass the standard quantum limit of measurement precision.<n>Here, we analytically demonstrate quantum-enhanced sensitivity for a broad class of distributed quantum probes.<n>We construct the corresponding optimal measurement strategies that achieve the ultimate precision limits.
  arXiv  Detail & Related papers  (2025-10-16T18:00:01Z)
• Detecting Entanglement via Split Spectroscopy in Many-Body Systems [3.8121150313479655]
  We propose split spectroscopy as an experimentally feasible technique for detecting entanglement of eigenstates in quantum many-body systems.<n>Our framework is illustrated using two paradigmatic spin models that undergo quantum phase transitions.<n>We show that the spectral entropy serves as a powerful indicator of quantum phase transitions and captures the scaling behavior of entanglement.
  arXiv  Detail & Related papers  (2025-08-12T07:49:51Z)
• Thermalization and Criticality on an Analog-Digital Quantum Simulator [133.58336306417294]
  We present a quantum simulator comprising 69 superconducting qubits which supports both universal quantum gates and high-fidelity analog evolution. We observe signatures of the classical Kosterlitz-Thouless phase transition, as well as strong deviations from Kibble-Zurek scaling predictions. We digitally prepare the system in pairwise-entangled dimer states and image the transport of energy and vorticity during thermalization.
  arXiv  Detail & Related papers  (2024-05-27T17:40:39Z)
• Proof-of-concept Quantum Simulator based on Molecular Spin Qudits [39.28601213393797]
  We show the first prototype quantum simulator based on an ensemble of molecular qudits and a radiofrequency broadband spectrometer. Results represent an important step towards the actual use of molecular spin qudits in quantum technologies.
  arXiv  Detail & Related papers  (2023-09-11T16:33:02Z)
• Measurement-induced entanglement and teleportation on a noisy quantum processor [105.44548669906976]
  We investigate measurement-induced quantum information phases on up to 70 superconducting qubits. We use a duality mapping, to avoid mid-circuit measurement and access different manifestations of the underlying phases. Our work demonstrates an approach to realize measurement-induced physics at scales that are at the limits of current NISQ processors.
  arXiv  Detail & Related papers  (2023-03-08T18:41:53Z)
• Integrated Quantum Optical Phase Sensor [48.7576911714538]
  We present a photonic integrated circuit fabricated in thin-film lithium niobate. We use the second-order nonlinearity to produce a squeezed state at the same frequency as the pump light and realize circuit control and sensing with electro-optics. We anticipate that on-chip photonic systems like this, which operate with low power and integrate all of the needed functionality on a single die, will open new opportunities for quantum optical sensing.
  arXiv  Detail & Related papers  (2022-12-19T18:46:33Z)
• Tunable photon-mediated interactions between spin-1 systems [68.8204255655161]
  We show how to harness multi-level emitters with several optical transitions to engineer photon-mediated interactions between effective spin-1 systems. Our results expand the quantum simulation toolbox available in cavity QED and quantum nanophotonic setups.
  arXiv  Detail & Related papers  (2022-06-03T14:52:34Z)
• Entanglement catalysis for quantum states and noisy channels [41.94295877935867]
  We investigate properties of entanglement and its role for quantum communication. For transformations between bipartite pure states, we prove the existence of a universal catalyst. We further develop methods to estimate the number of singlets which can be established via a noisy quantum channel.
  arXiv  Detail & Related papers  (2022-02-10T18:36:25Z)
• Quantum Phases of Matter on a 256-Atom Programmable Quantum Simulator [41.74498230885008]
  We demonstrate a programmable quantum simulator based on deterministically prepared two-dimensional arrays of neutral atoms. We benchmark the system by creating and characterizing high-fidelity antiferromagnetically ordered states. We then create and study several new quantum phases that arise from the interplay between interactions and coherent laser excitation.
  arXiv  Detail & Related papers  (2020-12-22T19:00:04Z)
• Scalable multiphoton quantum metrology with neither pre- nor post-selected measurements [0.0]
  We experimentally demonstrate a scalable protocol for quantum-enhanced optical phase estimation. The robustness of two-mode squeezed vacuum states against loss allows us to outperform schemes based on N00N states. Our work is important for quantum technologies that rely on multiphoton interference.
  arXiv  Detail & Related papers  (2020-11-04T18:11:33Z)
• On the capability of a class of quantum sensors [10.894655702718783]
  We investigate the capability of a class of quantum sensors which consist of either a single qubit or two qubits. A quantum sensor is coupled to a spin chain system to extract information of unknown parameters in the system.
  arXiv  Detail & Related papers  (2020-03-19T10:56:08Z)

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.