English
Related papers

Related papers: Improved Quantum Sensing by Spectral Design

200 papers

Incoherence in the controlled Hamiltonian is an important limitation on the precision of coherent control in quantum information processing. Incoherence can typically be modelled as a distribution of unitary processes arising from slowly…

Quantum Physics · Physics 2009-11-10 N. Boulant , S. Furuta , J. Emerson , T. F. Havel , D. G. Cory

We show how additional constraints, restricting the spectrum of the optimized pulse or confining the system dynamics, can be used to steer optimization in quantum control towards distinct solutions. Our examples are multi-photon excitation…

Quantum Physics · Physics 2013-11-18 José P. Palao , Daniel M. Reich , Christiane P. Koch

We describe a semidefinite relaxation method which finds lower bounds to the ground state energy of a quantum Hamiltonian subject to Hermitian linear constraints along with approximations of ground state expectation values. We show that…

Strongly Correlated Electrons · Physics 2026-05-29 Michael G. Scheer

The capacity to custom tailor the properties of quantum matter and materials is a central requirement for enlarging their range of possible functionalities. A particularly promising route is the use of driving protocols to engineer specific…

Quantum Physics · Physics 2025-02-19 Zhanpeng Fu , Roderich Moessner , Hongzheng Zhao , Marin Bukov

We consider quantum metrology with arbitrary prior knowledge of the parameter. We demonstrate that a single sensing two-level system can act as a virtual multi-level system that offers increased sensitivity in a Bayesian, single-shot,…

Quantum Physics · Physics 2017-05-03 P. Sekatski , M. Skotiniotis , W. Dür

In this paper, we propose a perceptually-guided visualization sharpening technique. We analyze the spectral behavior of an established comprehensive perceptual model to arrive at our approximated model based on an adapted weighting of the…

Graphics · Computer Science 2019-07-25 Liang Zhou , Rudolf Netzel , Daniel Weiskopf , Chris Johnson

Recently, the Hamiltonian Control Theory was used in [Boreux et al.] to increase the dynamic aperture of a ring particle accelerator having a localized thin sextupole magnet. In this letter, these results are extended by proving that a…

Accelerator Physics · Physics 2016-12-21 Jehan Boreux , Timoteo Carletti , Charalampos Skokos , Yannis Papaphilippou , Michel Vittot

We experimentally demonstrated a spectral imaging scheme with dual compressed sensing. With the dimensions of spectral and spatial information both compressed, the spectral image of a colored object can be obtained with only a single point…

Optics · Physics 2015-02-17 Xue-Feng Liu , Wen-Kai Yu , Xu-Ri Yao , Bin Dai , Long-Zhen Li , Chao Wang , Guang-Jie Zhai

We prove that estimating the ground state energy of a translationally-invariant, nearest-neighbour Hamiltonian on a 1D spin chain is QMAEXP-complete, even for systems of low local dimension (roughly 40). This is an improvement over the best…

Quantum Physics · Physics 2017-11-15 Johannes Bausch , Toby Cubitt , Maris Ozols

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

Recent advances in analog and digital quantum-simulation platforms have enabled exploration of the spectrum of entanglement Hamiltonians via variational algorithms. In this work we analyze the convergence properties of the variationally…

Quantum Physics · Physics 2025-05-16 Yanick S. Kind , Benedikt Fauseweh

Identifying the Hamiltonian of a quantum system from experimental data is considered. General limits on the identifiability of model parameters with limited experimental resources are investigated, and a specific Bayesian estimation…

Quantum Physics · Physics 2019-10-15 S. G. Schirmer , F. C. Langbein

Quantum optimal control represents a powerful technique to enhance the performance of quantum experiments by engineering the controllable parameters of the Hamiltonian. However, the computational overhead for the necessary optimization of…

Quantum control can be employed in quantum metrology to improve the precision limit for the estimation of unknown parameters. The optimal control, however, typically depends on the actual values of the parameters and thus needs to be…

Quantum Physics · Physics 2021-04-30 Han Xu , Lingna Wang , Haidong Yuan , Xin Wang

This paper proposes a new approach to construct high quality space-filling sample designs. First, we propose a novel technique to quantify the space-filling property and optimally trade-off uniformity and randomness in sample designs in…

Electronic transitions involving core-level orbitals offer a localized, atomic-site and element specific peek window into statistical systems such as molecular liquids. Although formally understood, the complex relation between structure…

Chemical Physics · Physics 2022-09-02 Johannes Niskanen , Anton Vladyka , J. Antti Kettunen , Christoph J. Sahle

Using a single quantum probe to sense other quantum objects offers distinct advantages but suffers from some limitations that may degrade the sensing precision severely, especially when the probe-target coupling is weak. Here we propose a…

Quantum Physics · Physics 2018-07-10 Yi-Nan Fang , Xing Xiao , Chang-Pu Sun , Wen Yang , Nan Zhao

Precision spectroscopy of solid-state systems is challenging due to inhomogeneous broadening. We describe a technique -- coherent quantum beats -- that enables the measurement of small frequency shifts within an inhomogeneously broadened…

Atomic Physics · Physics 2023-07-04 Harish D. Ramachandran , Julia E. Ford , Amar C. Vutha

We develop and analyze a new method for manipulation of energy in a quantum harmonic oscillator using coherent, e.g., electromagnetic, field and incoherent control. Coherent control is typically implemented by shaped laser pulse or tailored…

Quantum Physics · Physics 2024-03-28 Alexander N. Pechen , Sergey Borisenok , Alexander L. Fradkov

The reliable and precise generation of quantum unitary transformations is essential to the realization of a number of fundamental objectives, such as quantum control and quantum information processing. Prior work has explored the optimal…

Quantum Physics · Physics 2010-07-21 Michael Hsieh , Rebing Wu , Herschel Rabitz , Daniel Lidar