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Related papers: Advanced switching schemes in a Stark decelerator

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We present a scheme utilizing position-dependent ac Stark shifts for doing quantum logic with trapped ions. By a proper choice of direction, position and size, as well as power and frequency of a far-off-resonant Gaussian laser beam,…

Quantum Physics · Physics 2009-11-07 Peter Staanum , Michael Drewsen

To reduce the chattering and overestimation phenomena existing in classical adaptive sliding mode control, this paper presents a new class K_infinity function-based adaptive sliding mode control scheme. Two controllers are proposed in terms…

Systems and Control · Electrical Eng. & Systems 2020-12-07 J. Song , Z. Zuo , M. Basin

We present an on-line tuning strategy for the ISAC post-accelerator that pre-sets machine optics with a digital twin and then performs Bayesian optimization for steering under online operation with beam. The model computes end-to-end tunes…

Accelerator Physics · Physics 2026-02-25 O. Hassan , O. Shelbaya , P. M. Jung , O. Kester , T. Planche , W. Fedorko

Despite their frequent slow convergence, proximal gradient schemes are widely used in large-scale optimization tasks due to their tremendous stability, scalability, and ease of computation. In this paper, we develop and investigate a…

Computation · Statistics 2025-08-19 Nicholas C. Henderson , Ravi Varadhan

Unconditionally stable time stepping schemes are useful and often practically necessary for advancing parabolic operators in multi-scale systems. However, serious accuracy problems may emerge when taking time steps that far exceed the…

Computational Engineering, Finance, and Science · Computer Science 2024-03-05 Ronald M. Caplan , Craig D. Johnston , Lars K. S. Daldoff , Jon A. Linker

We analyze a quantum heat engine described by the full Dicke model. The system exhibit quantum phase transitions under certain conditions. We consider the system performing a Stirling thermodynamic cycle. We obtain an enhancement of…

Quantum Physics · Physics 2024-09-18 M. Aparicio Alcalde , E. Arias , N. F. Svaiter

Recent studies have shown that multi-step optimization based on Model Predictive Control (MPC) can effectively coordinate the increasing number of distributed renewable energy and storage resources in the power system. However, the…

Distributed, Parallel, and Cluster Computing · Computer Science 2016-06-02 Junyao Guo , Gabriela Hug , Ozan Tonguz

In a recent paper we presented a new ultra efficient numerical method for solving kinetic equations of the Boltzmann type (G. Dimarco, R. Loubere, Towards an ultra efficient kinetic scheme. Part I: basics on the 689 BGK equation, J. Comp.…

Numerical Analysis · Mathematics 2015-06-12 Giacomo Dimarco , Raphaël Loubere

Cold, velocity-controlled molecular beams consisting of a single quantum state promise to be a powerful tool for exploring molecular scattering interactions. In recent years, Stark deceleration has emerged as one of the main methods for…

We propose new restarting strategies for accelerated gradient and accelerated coordinate descent methods. Our main contribution is to show that the restarted method has a geometric rate of convergence for any restarting frequency, and so it…

Optimization and Control · Mathematics 2016-09-26 Olivier Fercoq , Zheng Qu

We propose a new selection rule for the coordinate selection in coordinate descent methods for huge-scale optimization. The efficiency of this novel scheme is provably better than the efficiency of uniformly random selection, and can reach…

Machine Learning · Computer Science 2017-06-27 Sebastian U. Stich , Anant Raj , Martin Jaggi

Operator splitting methods tailored to coupled linear port-Hamiltonian systems are developed. We present algorithms that are able to exploit scalar coupling, as well as multirate potential of these coupled systems. The obtained algorithms…

Numerical Analysis · Mathematics 2025-01-14 Jan Lorenz , Tom Zwerschke , Michael Günther , Kevin Schäfers

There is currently an increasing interest in developing efficient solvers for phase-field modeling of brittle fracture. The governing equations for this problem originate from a constrained minimization of a non-convex energy functional,…

Two mechanisms have recently been proposed that can significantly speed up finding distant improving solutions via mutation, namely using a random mutation rate drawn from a heavy-tailed distribution ("fast mutation", Doerr et al. (2017))…

Neural and Evolutionary Computing · Computer Science 2023-04-20 Benjamin Doerr , Amirhossein Rajabi

An important aspect of the recently introduced transient uncoupling scheme is that it induces synchronization for large values of coupling strength at which the coupled chaotic systems resist synchronization when continu- ously coupled.…

Chaotic Dynamics · Physics 2018-06-13 Anupam Ghosh , Prakhar Godara , Sagar Chakraborty

We present an alternative scheme for the generation of a 2-qubit quantum gate interaction between laser-cooled trapped ions. The scheme is based on the AC Stark shift (lightshift) induced by laser light resonant with the ionic transition…

Quantum Physics · Physics 2009-11-06 D. Jonathan , M. B. Plenio , P. L. Knight

We demonstrate the deceleration of heavy polar molecules in low-field seeking states by combining a cryogenic source and a travelling-wave Stark decelerator. The cryogenic source provides a high intensity beam with low speed and…

This is one of our series papers on multistep schemes for solving forward backward stochastic differential equations (FBSDEs) and related problems. Here we extend (with non-trivial updates) our multistep schemes in [W. Zhao, Y. Fu and T.…

Numerical Analysis · Mathematics 2015-02-12 Kong Tao , Weidong Zhao , Tao Zhou

In the following paper we present a new type of optimization algorithms adapted for neural network training. These algorithms are based upon sequential operator splitting technique for some associated dynamical systems. Furthermore, we…

Machine Learning · Computer Science 2020-03-24 Cristian Daniel Alecsa , Titus Pinta , Imre Boros

Decentralized solutions to finite-sum minimization are of significant importance in many signal processing, control, and machine learning applications. In such settings, the data is distributed over a network of arbitrarily-connected nodes…

Machine Learning · Computer Science 2019-11-14 Ran Xin , Soummya Kar , Usman A. Khan