English
Related papers

Related papers: Quantum enhanced estimation of a multi-dimensional…

200 papers

We consider the problem of quantum multi-parameter estimation with experimental constraints and formulate the solution in terms of a convex optimization. Specifically, we outline an efficient method to identify the optimal strategy for…

Quantum Physics · Physics 2013-05-29 Kevin C. Young , Mohan Sarovar , Robert Kosut , K. Birgitta Whaley

Incompatible, i.e. non-jointly measurable quantum measurements are a necessary resource for many information processing tasks. It is known that increasing the number of distinct measurements usually enhances the incompatibility of a…

Quantum Physics · Physics 2023-09-28 Lucas Tendick , Hermann Kampermann , Dagmar Bruß

We provide formulas for invariants defined on a tensor product of defining representations of unitary groups, under the action of the product group. This situation has a physical interpretation, as it is related to the quantum mechanical…

Representation Theory · Mathematics 2011-11-01 Michael W. Hero , Jeb F. Willenbring , Lauren Kelly Williams

Measuring entanglement is a demanding task in the field of quantum computation and quantum information theory. Recently, some authors experimentally demonstrated an embedding quantum simulator, using it to efficiently measure two-qubit…

Quantum Physics · Physics 2018-11-01 Saeed Haddadi , Mohammad Bohloul

Quantum metrology aims to enhance measurement precision beyond the classical limit by leveraging quantum resources. Unlike multi-parameter dynamic quantum metrology, many questions regarding multiparameter quantum metrology at thermal…

Quantum Physics · Physics 2026-05-20 Zhu Cao

We show that when a suitable entanglement generating unitary operator depending on a parameter is applied on N qubits in parallel, and an appropriate observable is measured, a precision of order 2 raised to the power (-N) in estimating the…

Quantum Physics · Physics 2013-05-29 S. M. Roy , Samuel L. Braunstein

Quantum technologies exploit entanglement to revolutionize computing, measurements, and communications. This has stimulated the research in different areas of physics to engineer and manipulate fragile many-particle entangled states.…

Quantum Physics · Physics 2018-11-13 Luca Pezzè , Augusto Smerzi , Markus K. Oberthaler , Roman Schmied , Philipp Treutlein

Preparation of a non-classically correlated state is the first step of any quantum-enhanced interferometric protocol. An efficient method is the one-axis twisting, which entangles a collection of initially uncorrelated particles by means of…

Quantum Physics · Physics 2015-10-28 K. Gietka , P. Szankowski , T. Wasak , J. Chwedenczuk

The power of quantum sensing rests on its ultimate precision limit, quantified by the quantum Cramer-Rao bound (QCRB), which can surpass classical bounds. In multi-parameter estimation, the QCRB is not always saturated as the quantum nature…

Quantum Physics · Physics 2024-05-24 Changhao Li , Mo Chen , Paola Cappellaro

Rapidly growing capabilities of quantum simulators to probe quantum many-body phenomena require new methods to characterize increasingly complex states. We present a protocol that constrains quantum states by experimentally measured…

Quantum Physics · Physics 2025-09-22 Henry Froland , Torsten V. Zache , Robert Ott , Niklas Mueller

A quantum metrology protocol for parameter estimation is typically comprised of three stages: probe state preparation, sensing and then readout, where the time required for the first and last stages is usually neglected. In the present work…

Quantum Physics · Physics 2018-01-11 Anthony J. Hayes , Shane Dooley , William J. Munro , Kae Nemoto , Jacob Dunningham

We argue that it is possible in principle to reduce the uncertainty of an atomic magnetometer by double-passing a far-detuned laser field through the atomic sample as it undergoes Larmor precession. Numerical simulations of the quantum…

Quantum Physics · Physics 2009-06-17 Bradley A. Chase , Ben Q. Baragiola , Heather L. Partner , Brigette D. Black , JM Geremia

Measurements with randomly chosen settings determine many important properties of quantum states without the need for a shared reference frame or calibration. They naturally emerge in the context of quantum communication and quantum…

Measuring entanglement is a demanding task that usually requires full tomography of a quantum system, involving a number of observables that grows exponentially with the number of parties. Recently, it was suggested that adding a single…

Quantum systems allow one to sense physical parameters beyond the reach of classical statistics---with resolutions greater than $1/N$, where $N$ is the number of constituent particles independently probing a parameter. In the canonical…

We propose a quantum-enhanced iterative (with $K$ steps) measurement scheme based on an ensemble of $N$ two-level probes which asymptotically approaches the Heisenberg limit $\delta_K \propto R^{-K/(K+1)}$, $R$ the number of quantum…

Quantum Physics · Physics 2014-01-29 A. V. Lebedev , P. Treutlein , G. Blatter

Reliable methods for the classification and quantification of quantum entanglement are fundamental to understanding its exploitation in quantum technologies. One such method, known as Separable Neural Network Quantum States (SNNS), employs…

Quantum Physics · Physics 2021-06-15 Cillian Harney , Mauro Paternostro , Stefano Pirandola

Quantifying entanglement is an important issue in quantum information theory. Here we consider the entanglement measures through the trace norm in terms of two methods, the modified measure and the extended measure for bipartite states. We…

Quantum Physics · Physics 2023-02-09 Xian Shi , Lin Chen , Yixuan Liang

Quantum phase estimation is one of the most powerful quantum primitives. This work proposes a new approach for the problem of multiple eigenvalue estimation: Quantum Multiple Eigenvalue Gaussian filtered Search (QMEGS). QMEGS leverages the…

Quantum Physics · Physics 2024-10-02 Zhiyan Ding , Haoya Li , Lin Lin , HongKang Ni , Lexing Ying , Ruizhe Zhang

We investigate the problem of determining the parameters that describe a quantum channel. It is assumed that the users of the channel have at best only partial knowledge of it and make use of a finite amount of resources to estimate it. We…