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Related papers: Optimal estimation of quantum dynamics

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We consider the dynamics of a spin-1/2 particle constrained to move in an arbitrary space curve with an external electric and magnetic field applied. With the aid of gauge theory, we successfully decouple the tangential and normal dynamics…

Mesoscale and Nanoscale Physics · Physics 2020-06-24 Guo-Hua Liang , Yong-Long Wang , Meng-Yun Lai , Hao Zhao , Hong-Shi Zong , Hui Liu

For the precise estimation of the unknown quantum state, the independent samples should be prepared. Can we reduce the error of the estimation by the measurement using the quantum correlation between every sample? In this paper, this…

Quantum Physics · Physics 2007-05-23 Masahito Hayashi

This thesis presents an efficient quantum algorithm and explicit circuits for generating eigenstates of arbitrary SU(2) and SU(3) representations. These include a wide variety of highly entangled states. The algorithm uses Schur transform…

Quantum Physics · Physics 2013-09-12 Satya Sainadh U

Precise estimation of physical parameters underpins both scientific discovery and technological development. A central goal of quantum metrology and sensing is to exploit quantum resources like entanglement to devise optimal strategies for…

Quantum Physics · Physics 2026-03-09 Zhao-Yi Zhou , Da-Jian Zhang

We study the ability to implement unitary maps on states of the $I=9/2$ nuclear spin in \textsuperscript{87}Sr, a $d=10$ dimensional (qudecimal) Hilbert space, using quantum optimal control. Through a combination of nuclear spin-resonance…

Quantum Physics · Physics 2022-11-30 Sivaprasad Omanakuttan , Anupam Mitra , Michael J. Martin , Ivan H Deutsch

We study quantum metrology for unitary dynamics. Analytic solutions are given for both the optimal unitary state preparation starting from an arbitrary mixed state and the corresponding optimal measurement precision. This represents a…

Quantum Physics · Physics 2019-12-30 Lukas J. Fiderer , Julien M. E. Fraïsse , Daniel Braun

We derive an optimal bound on the sum of entropic uncertainties of two or more observables when they are sequentially measured on the same ensemble of systems. This optimal bound is shown to be greater than or equal to the bounds derived in…

Quantum Physics · Physics 2009-11-07 M. D. Srinivas

We present a framework that formulates the quest for the most efficient quantum state tomography scheme as an optimization problem which can be solved numerically. This approach can be applied to a broad spectrum of relevant setups…

Quantum Physics · Physics 2021-12-17 Violeta N. Ivanova-Rohling , Guido Burkard , Niklas Rohling

We consider the problem of controlling in minimum time a two-level quantum system which can be subject to a drift. The control is assumed to be bounded in magnitude, and to affect two or three independent generators of the dynamics. We…

Quantum Physics · Physics 2015-10-28 Raffaele Romano

Finding the ground state of a quantum mechanical system can be formulated as an optimal control problem. In this formulation, the drift of the optimally controlled process is chosen to match the distribution of paths in the Feynman--Kac…

Quantum Physics · Physics 2020-06-17 Ariel Barr , Willem Gispen , Austen Lamacraft

This paper tackles the problem of integrated task and kinodynamic motion planning in uncertain environments. We consider a robot with nonlinear dynamics tasked with a Linear Temporal Logic over finite traces ($\ltlf$) specification…

Robotics · Computer Science 2026-04-02 Qi Heng Ho , Zachary N. Sunberg , Morteza Lahijanian

The purpose of this paper is to introduce techniques of obtaining optimal ways to determine a d-level quantum state or distinguish such states. It entails designing constrained elementary measurements extracted from maximal abelian subsets…

Quantum Physics · Physics 2021-04-28 S. Chaturvedi , Sibasish Ghosh , K. R. Parthasarathy , Ajit Iqbal Singh

The optimal control of unitary transformations is a fundamental problem in quantum control theory and quantum information processing. The feasibility of performing such optimizations is determined by the computational and control resources…

Quantum Physics · Physics 2015-05-19 Katharine W. Moore , Raj Chakrabarti , Gregory Riviello , Herschel Rabitz

We develop an asymptotic theory of estimation of a shift parameter in a pure quantum state to study the relation between entangled and unentangled covariant estimates in the analytically most transparent way. After recollecting basics of…

Quantum Physics · Physics 2011-11-09 A. S. Holevo

A quantum gate is realized by specific unitary transformations operating on states representing qubits. Considering a quantum system employed as an element in a quantum computing scheme, the task is therefore to enforce the pre-specified…

Quantum Physics · Physics 2007-05-23 Jose P. Palao , Ronnie Kosloff

With the advance of quantum information technology, the question of how to most efficiently test quantum circuits is becoming of increasing relevance. Here we introduce the statistics of lengths of measurement sequences that allows one to…

Quantum Physics · Physics 2022-10-27 N. Milazzo , D. Braun , O. Giraud

We find the optimal scheme for quantum phase estimation in the presence of loss when no a priori knowledge on the estimated phase is available. We prove analytically an explicit lower bound on estimation uncertainty, which shows that, as a…

Quantum Physics · Physics 2010-11-09 Jan Kolodynski , Rafal Demkowicz-Dobrzanski

Optimization under uncertainty deals with the problem of optimizing stochastic cost functions given some partial information on their inputs. These problems are extremely difficult to solve and yet pervade all areas of technological and…

Statistical Mechanics · Physics 2015-03-13 Fabrizio Altarelli , Alfredo Braunstein , Abolfazl Ramezanpour , Riccardo Zecchina

We consider Bayesian estimate of static magnetic field, characterized by a prior Gaussian probability distribution, in systems of a few electron quantum dot spins interacting with infinite temperature spin environment via hyperfine…

Quantum Physics · Physics 2016-11-15 Paweł Mazurek , Michał Horodecki , Łukasz Czekaj , Paweł Horodecki

The aim of this paper is to formulate and analyze numerical discretizations of charged-particle dynamics (CPD) in a strong nonuniform magnetic field. A strategy is firstly performed for the two dimensional CPD to construct the…

Numerical Analysis · Mathematics 2022-05-18 Bin Wang , Yaolin Jiang