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We propose a scalable encoding of combinatorial optimization problems with arbitrary connectivity, including higher-order terms, on arrays of trapped neutral atoms requiring only a global laser drive. Our approach relies on modular…

Quantum Physics · Physics 2024-10-08 Martin Lanthaler , Kilian Ender , Clemens Dlaska , Wolfgang Lechner

Photonic topology optimization is a technique used to find the electric permittivity distribution of a device that optimizes an electromagnetic figure-of-merit. Two common techniques are used: continuous density-based optimizations that…

Applied Physics · Physics 2021-07-21 Conner Ballew , Gregory Roberts , Tianzhe Zheng , Andrei Faraon

Self-compensated comagnetometers, employing overlapping samples of spin-polarized alkali and noble gases (for example K-$^3$He) are promising sensors for exotic beyond-the-standard-model fields and high-precision metrology such as rotation…

The design of divertor targets and baffles for optimal heat and particle exhaust from magnetically confined fusion plasmas requires a combination of fast, low-fidelity models (such as EMC3-lite [1]) for scoping studies and high-fidelity…

Computational Physics · Physics 2025-02-14 H. Frerichs , D. Boeyaert , Y. Feng , K. A. Garcia

Discrete optimization belongs to the set of $\mathcal{NP}$-hard problems, spanning fields such as mixed-integer programming and combinatorial optimization. A current standard approach to solving convex discrete optimization problems is the…

Machine Learning · Computer Science 2024-02-28 Kyle Mana , Fernando Acero , Stephen Mak , Parisa Zehtabi , Michael Cashmore , Daniele Magazzeni , Manuela Veloso

Stellarators are generically small current and low plasma beta ($\beta= p/B^2\ll1$) devices. Often the construction of vacuum magnetic fields with good magnetic surfaces is the starting point for an equilibrium calculation. Although in…

Plasma Physics · Physics 2019-04-17 Wrick Sengupta , Harold Weitzner

This paper considers an optimization problem for a dynamical system whose evolution depends on a collection of binary decision variables. We develop scalable approximation algorithms with provable suboptimality bounds to provide…

Optimization and Control · Mathematics 2016-10-31 Insoon Yang , Samuel A. Burden , Ram Rajagopal , S. Shankar Sastry , Claire J. Tomlin

Magnetic gels and elastomers are promising candidates to construct reversibly excitable soft actuators, triggered from outside by magnetic fields. These magnetic fields induce or alter the magnetic interactions between discrete rigid…

Soft Condensed Matter · Physics 2019-10-02 Lukas Fischer , Andreas M. Menzel

We present the standard electromagnetic Particle-in-Cell method, starting from the discrete approximation of derivatives on a uniform grid. The application to second-order, centered, finite-difference discretization of the equations of…

Computational Physics · Physics 2020-08-18 J. L. Vay

We consider a problem relating to magnetic confinement devices known as stellarators. Plasma is confined by magnetic fields generated by current-carrying coils, and here we investigate how closely to the plasma they need to be positioned.…

Analysis of PDEs · Mathematics 2021-08-18 Adam J. Golab , James C. Robinson , José L. Rodrigo

We consider the Vlasov-Poisson system that is equipped with an external magnetic field to describe the time evolution of the distribution function of a plasma. An optimal control problem where the external magnetic field is the control…

Optimization and Control · Mathematics 2021-10-12 Patrik Knopf , Jörg Weber

The confinement of heat in the core of a magnetic fusion reactor is optimised using a multidimensional optimisation algorithm. For the first time in such a study, the loss of heat due to turbulence is modelled at every stage using…

Plasma Physics · Physics 2018-10-24 E. G. Highcock , N. R. Mandell , M. Barnes , W. Dorland

To better understand the dependence of the magnetic field structure in the plasma edge on the plasma boundary shape, in the context of X-point and island divertor designs, we define and develop a class of stellarators called umbilic…

Plasma Physics · Physics 2026-01-28 R. Gaur , D. Panici , T. M. Elder , M. Landreman , K. E. Unalmis , Y. Elmacioglu , D. Dudt , R. Conlin , E. Kolemen

A popular approach in combinatorial optimization is to model problems as integer linear programs. Ideally, the relaxed linear program would have only integer solutions, which happens for instance when the constraint matrix is totally…

Data Structures and Algorithms · Computer Science 2009-09-29 Christoph Durr , Mathilde Hurand

Permanent magnet-assisted synchronous reluctance motors (PMSynRM) have a significantly higher average torque than synchronous reluctance motors. Thus, determining an optimal design results in a multi-material topology optimization problem,…

Optimization and Control · Mathematics 2026-04-01 Thomas Gauthey , Peter Gangl , Maya Hage Hassan

Hybrid magnetic shields with both active field generating components and high-permeability magnetic shielding are increasingly needed for a variety of technologies and experiments that require precision-controlled magnetic field…

Applied Physics · Physics 2021-06-04 M. Packer , P. J. Hobson , N. Holmes , J. Leggett , P. Glover , M. J. Brookes , R. Bowtell , T. M. Fromhold

Magnetically-sensitive experiments and newly-developed quantum technologies with integrated high-permeability magnetic shields require increasing control of their magnetic field environment and reductions in size, weight, power and cost.…

An automated algorithm to construct island divertors for stellarators is presented and is used to find divertors that meet heat flux requirements determined by engineering and material limits. The algorithm uses just two initial conditions:…

Plasma Physics · Physics 2026-03-02 Avigdor Veksler , Aaron Bader , Heinke Frerichs , Elizabeth Paul

Nuclear fusion using magnetic confinement holds promise as a viable method for sustainable energy. However, most fusion devices have been experimental and as we move towards energy reactors, we are entering into a new paradigm of…

Plasma Physics · Physics 2023-10-04 Timothy Nunn , Vignesh Gopakumar , Sebastien Kahn

We apply inverse design methods to produce two-dimensional triangular-lattice plasma metamaterial (PMM) devices which are then constructed and demonstrated experimentally. Finite difference frequency domain simulations are used along with…

Plasma Physics · Physics 2023-10-09 Jesse A. Rodriguez , Mark A. Cappelli