English
Related papers

Related papers: Projected Optimal Sensors from Operator Orbits

200 papers

To optimize the entanglement detection, we formulate the metrologically operational entanglement condition in quantum Fisher information by maximizing the QFI on the measurement orbit. Specifically, we consider two classes of typical local…

Quantum Physics · Physics 2024-10-28 Ao-Xiang Liu , Ma-Cheng Yang , Cong-Feng Qiao

We show how to verify the metrological usefulness of quantum states based on the expectation values of an arbitrarily chosen set of observables. In particular, we estimate the quantum Fisher information as a figure of merit of metrological…

Quantum Physics · Physics 2017-04-25 Iagoba Apellaniz , Matthias Kleinmann , Otfried Gühne , Geza Toth

Algorithms based on non-unitary evolution have attracted much interest for ground state preparation on quantum computers. One recently proposed method makes use of ancilla qubits and controlled unitary operators to implement weak…

Quantum Physics · Physics 2025-12-25 Tobias Stollenwerk , Stuart Hadfield

We construct uncertainty relation for arbitrary finite dimensional PT invariant non-Hermitian quantum systems within a special inner product framework. This construction is led by good observables which are a more general class of…

Quantum Physics · Physics 2023-04-11 Namrata Shukla , Ranjan Modak , Bhabani Prasad Mandal

We address parameter estimation for complex/structured systems and suggest an effective estimation scheme based on continuous-variables quantum probes. In particular, we investigate the use of a single bosonic mode as a probe for Ohmic…

Quantum Physics · Physics 2018-01-31 Matteo Bina , Federico Grasselli , Matteo G. A. Paris

Quantum metrology and sensing seek advantage in estimating an unknown parameter of some quantum state or channel, using entanglement such as spin squeezing produced by one-axis twists or other quantum resources. In particular, qubit phase…

Quantum Physics · Physics 2024-05-29 Tyler G. Thurtell , Akimasa Miyake

We investigate the optimal quantum state for an atomic gyroscope based on a three-site Bose-Hubbard model. In previous studies, various states such as the uncorrelated state, the BAT state and the NOON state are employed as the probe states…

Quantum Physics · Physics 2020-12-02 Lei Shao , Weiyao Li , Xiaoguang Wang

Non-stabilizerness (colloquially "magic") characterizes genuinely quantum (beyond-Clifford) operations necessary for preparation of quantum states, and can be measured by stabilizer R\'enyi entropy (SRE). For permutationally symmetric…

Quantum Physics · Physics 2026-01-23 Tanausú Hernández-Yanes , Piotr Sierant , Jakub Zakrzewski , Marcin Płodzień

We introduce a semidefinite programming algorithm to find the minimal quantum Fisher information compatible with an arbitrary dataset of mean values. This certification task allows one to quantify the resource content of a quantum system…

Fisher information provides a rigorous theoretical benchmark for evaluating quantum sensor sensitivity; however, a comprehensive framework for quantifying the fundamental limits of Rydberg-atom microwave electrometers remains lacking. In…

Optics · Physics 2026-03-04 Chen-Rong Liu , Runxia Tao , Xiang Lv , Ying Dong , Chuang Li , Binbin Wei , Mingti Zhou

Small, controllable quantum systems, known as quantum probes, have been proposed to estimate various parameters characterizing complex systems such as the environments of quantum systems. These probes, prepared in some initial state, are…

Quantum Physics · Physics 2021-07-21 Hamza Ather , Adam Zaman Chaudhry

In its simplest form, decoherence occurs when a quantum state is entangled with a second state, but the results of measurements made on the second state are not accessible. As the second state has effectively "measured" the first, in this…

Quantum Physics · Physics 2017-05-02 Samuel P. Nolan , Simon A. Haine

We investigate the potential of weak measurement and post-selection to enhance measurement sensitivity when the initial probe state is mixed. In our framework, the mixedness of the probe's density operator is controlled by temperature. We…

Quantum Physics · Physics 2025-09-05 Lorena Ballesteros Ferraz , Alexandre Matzkin , Alok Kumar Pan

Sensing networks underpin applications from fundamental physics to real-world engineering. Recently, distributed quantum sensing (DQS) has been investigated to boost the sensing performance, yet current schemes typically rely on entangled…

Quantum Physics · Physics 2026-01-22 Binke Xia , Zhaotong Cui , Jingzheng Huang , Yuxiang Yang , Guihua Zeng

Quantum state estimation is important for various quantum information processes, including quantum communications, computation, and metrology, which require the characterization of quantum states for evaluation and optimization. We present…

Quantum Physics · Physics 2026-04-15 C. Vargas , L. Pereira , A. Delgado

Quantum sensors based on single solid-state spins promise a unique combination of sensitivity and spatial resolution. The key challenge in sensing is to achieve minimum estimation uncertainty within a given time and with a high dynamic…

The quantum rotor represents, after the harmonic oscillator, the next obvious quantum system to study the complementary pair of variables: the angular momentum and the unitary shift operator in angular momentum. Proper quantification of…

Quantum Physics · Physics 2024-08-13 Ladislav Mišta , Matouš Mišta , Zdeněk Hradil

We introduce a genetic algorithm that designs quantum optics experiments for engineering quantum states with specific properties. Our algorithm is powerful and flexible, and can easily be modified to find methods of engineering states for a…

Quantum Physics · Physics 2023-05-01 Rosanna Nichols , Lana Mineh , Jesús Rubio , Jonathan C. F. Matthews , Paul A. Knott

The precision advantages offered by harnessing the quantum states of sensors can be readily compromised by noise. However, when the noise has a different spatial function than the signal of interest, recent theoretical work shows how the…

We identify the large-$N$ scaling of the metrological quantum gain offered by over-squeezed spin states that are accessible by one-axis-twisting, as a function of the preparation time. We further determine how the scaling is modified by…

Quantum Physics · Physics 2022-02-03 Y. Baamara , A. Sinatra , M. Gessner