English
Related papers

Related papers: Time complexity in preparing metrologically useful…

200 papers

We derive an upper bound for the time needed to implement a generic unitary transformation in a $d$ dimensional quantum system using $d$ control fields. We show that given the ability to control the diagonal elements of the Hamiltonian,…

Quantum Physics · Physics 2020-04-22 Juneseo Lee , Christian Arenz , Daniel Burgarth , Herschel Rabitz

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 many-body interactions can induce quantum entanglement among particles, rendering them valuable resources for quantum-enhanced sensing. In this work, we derive a universal and fundamental bound for the growth of the quantum Fisher…

Quantum Physics · Physics 2024-03-07 Hai-Long Shi , Xi-Wen Guan , Jing Yang

We establish a relationship between the correlations in a many-qubit mixed state and the minimum circuit depth needed for its preparation. If the mutual information between two subsystems exceeds the mutual information between one of those…

Quantum Physics · Physics 2025-10-03 Max McGinley , Samuel J. Garratt

Minimizing the time required for quantum state preparation is crucial to mitigate decoherence and enable practical quantum algorithms on near-term hardware. In this work, we introduce a technique for quantum state preparation in…

Quantum Physics · Physics 2026-02-25 K. De La Ossa Doria , T. Merlo Vergara , D. Goyeneche

In short-range interacting systems, the speed at which entanglement can be established between two separated points is limited by a constant Lieb-Robinson velocity. Long-range interacting systems are capable of faster entanglement…

Dissipative quantum algorithms for state preparation in many-body systems are increasingly recognised as promising candidates for achieving large quantum advantages in application-relevant tasks. Recent advances in algorithmic,…

Quantum Physics · Physics 2026-04-21 Štěpán Šmíd , Richard Meister , Mario Berta , Roberto Bondesan

In this paper we explore the possibility of performing Heisenberg limited quantum metrology of a phase, without any prior, by employing only maximally entangled states. Starting from the estimator introduced by Higgins et al. in New J.…

Quantum Physics · Physics 2020-10-27 Federico Belliardo , Vittorio Giovannetti

Cat states are a valuable resource for quantum metrology applications, promising to enable sensitivity down to the Heisenberg limit. Moreover, Schr\"odinger cat states, based on a coherent superposition of coherent states, show robustness…

Quantum Physics · Physics 2023-12-11 S. Zhao , M. G. Krauss , T. Bienaime , S. Whitlock , C. P. Koch , S. Qvarfort , A. Metelmann

It is a specific type of quantum correlated state that achieves optimal precision in parameterestimation under unitary encoding. We consider the potential experimental limitation on probe entanglement, and find a relation between achievable…

Quantum Physics · Physics 2026-01-06 Debarupa Saha , Ujjwal Sen

We propose a robust approach to spin squeezing with local interactions that approaches the Heisenberg limit of phase sensitivity. To generate the requisite entanglement, we generalize the paradigmatic two-axis countertwisting Hamiltonian --…

In this paper, we derive sharp lower bounds, also known as quantum speed limits, for the time it takes to transform a quantum system into a state such that an observable assumes its lowest average value. We assume that the system is…

Quantum Physics · Physics 2021-06-02 Dan Allan , Niklas Hörnedal , Ole Andersson

Studies of quantum metrology have shown that the use of many-body entangled states can lead to an enhancement in sensitivity when compared to product states. In this paper, we quantify the metrological advantage of entanglement in a setting…

Measurements take a singular role in quantum theory. While they are often idealized as an instantaneous process, this is in conflict with all other physical processes in nature. In this Letter, we adopt a standpoint where the interaction…

Quantum Physics · Physics 2023-11-15 Nathan Shettell , Federico Centrone , Luis Pedro García-Pintos

We consider the two-step method [A. R. Kuzmak and V. M. Tkachuk, Phys. Lett. A 378 (2014) 1469] for preparation of an arbitrary quantum gate on two spins with anisotropic Heisenberg interaction. At the first step, the system evolves during…

Quantum Physics · Physics 2018-09-20 A. R. Kuzmak

This thesis examines some of the more fundamental requirements of a successful quantum computation, namely the ability to transmit quantum information with maximum efficiency, and the creation of entanglement. I focus specifically on…

Quantum Physics · Physics 2009-09-30 Martina Avellino

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…

Finding minimal time and establishing the structure of the corresponding optimal controls which can transfer a given initial state of a quantum system into a given target state is a key problem of quantum control. In this work, this problem…

Quantum Physics · Physics 2025-02-21 L. V. Lokutsievskiy , A. N. Pechen , M. I. Zelikin

A candidate application for quantum computers is to simulate the low-temperature properties of quantum systems. For this task, there is a well-studied quantum algorithm that performs quantum phase estimation on an initial trial state that…

Quantum Physics · Physics 2024-11-04 Chi-Fang , Chen , Alexander M. Dalzell , Mario Berta , Fernando G. S. L. Brandão , Joel A. Tropp

Fermionic ansatz state preparation is a critical subroutine in many quantum algorithms such as Variational Quantum Eigensolver for quantum chemistry and condensed matter applications. The shallowest circuit depth needed to prepare Slater…

Quantum Physics · Physics 2023-08-22 Chong Hian Chee , Daniel Leykam , Adrian M. Mak , Dimitris G. Angelakis