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Related papers: Model identification for spin networks

200 papers

Using analytic and numerical methods, we study a $2d$ Hamiltonian model of interacting particles carrying ferro-magnetically coupled continuous spins which are also locally coupled to their own velocities. This model has been characterised…

Statistical Mechanics · Physics 2020-05-14 Mathias Casiulis , Marco Tarzia , Leticia F. Cugliandolo , Olivier Dauchot

We present a Hamiltonian that can be used for amplifying the signal from a quantum state, enabling the measurement of a macroscopic observable to determine the state of a single spin. We prove a general mapping between this Hamiltonian and…

Quantum Physics · Physics 2007-05-23 A. Kay

In this work, we study the identifiability of network structures (i.e., topologies) for networked nonlinear systems when partial measurements of the nodal dynamics are taken. We explore scenarios where different candidate structures can…

Systems and Control · Electrical Eng. & Systems 2026-03-13 Jaidev Gill , Jing Shuang Li

The recent development in the field of 2D magnetic materials urges reliable theoretical methodology for determination of magnetic properties. Among the available methods, ab initio four-state energy mapping based on Density Functional…

Mesoscale and Nanoscale Physics · Physics 2020-08-05 Denis Sabani , Cihan Bacaksiz , Milorad Milosevic

We introduce a generalizable framework for learning to identify effective Hamiltonians directly from experimental data in solid-state quantum systems. Our approach is based on a physics-informed neural network architecture that embeds…

Mesoscale and Nanoscale Physics · Physics 2026-03-04 Jarosław Pawłowski , Mateusz Krawczyk

The problem of identifiability of model parameters for open quantum systems is considered by investigating two-level dephasing systems. We discuss under which conditions full information about the Hamiltonian and dephasing parameters can be…

Quantum Physics · Physics 2015-01-15 Er-ling Gong , Weiwei Zhou , S. G. Schirmer , Zhi-Qiang Sun , Ming Zhang

We propose a method to perform precision measurements of the interaction parameters in systems of N ultra-cold spin 1/2 atoms. The spectroscopy is realized by first creating a coherent spin superposition of the two relevant internal states…

Other Condensed Matter · Physics 2009-11-13 A. M. Rey , L. Jiang , M. D. Lukin

Despite the successes of machine learning methods in physical sciences, prediction of the Hamiltonian, and thus electronic properties, is still unsatisfactory. Here, based on graph neural network architecture, we present an extendable…

Materials Science · Physics 2023-01-12 Mao Su , Ji-Hui Yang , Hong-Jun Xiang , Xin-Gao Gong

The spectral properties of $su(2)$ Hamiltonians are studied for energies near the critical classical energy $\epsilon_c$ for which the corresponding classical dynamics presents hyperbolic points (HP). A general method leading to an…

Quantum Physics · Physics 2009-11-13 Pedro Ribeiro , Thierry Paul

We develop a structured theoretical framework used in our recent articles [Eur. Phys. J. B 92, 93 (2019) and Phys. Rev. B 101, 094427 (2020)] to characterize the unusual behavior of the magnetic spectrum, magnetization and magnetic…

Strongly Correlated Electrons · Physics 2022-05-19 M. Georgiev , H. Chamati

We determine the complete set of generalized spin squeezing inequalities. These are entanglement criteria that can be used for the experimental detection of entanglement in a system of spin-1/2 particles in which the spins cannot be…

Quantum Physics · Physics 2011-11-09 Geza Toth , Christian Knapp , Otfried Gühne , Hans J. Briegel

Identifying the nature of interactions in a quantum system is essential in understanding any physical phenomena. Acquiring information on the Hamiltonian can be a tough challenge in many-body systems because it generally requires access to…

Quantum Physics · Physics 2009-10-09 Daniel Burgarth , Koji Maruyama

The characterization and manipulation of deposited magnetic clusters or molecules on surfaces is a prerequisite for their future utilization. In recent years techniques like spin-flip inelastic electron tunneling spectroscopy using a…

Strongly Correlated Electrons · Physics 2019-03-25 H. -T. Langwald , J. Schnack

Quantum networks are an integral component in performing efficient computation and communication tasks that are not accessible using classical systems. A key aspect in designing an effective and scalable quantum network is generating…

Quantum Physics · Physics 2018-07-10 Sudipto Singha Roy , Himadri Shekhar Dhar , Debraj Rakshit , Aditi Sen De , Ujjwal Sen

We investigate the problem of determining the Hamiltonian of a locally interacting open-quantum system. To do so, we construct model estimators based on inverting a set of stationary, or dynamical, Heisenberg-Langevin equations of motion…

Quantum Physics · Physics 2020-08-19 Eugene F. Dumitrescu , Pavel Lougovski

We present a universal quantum Monte Carlo algorithm for simulating arbitrary high-spin (spin greater than 1/2) Hamiltonians, based on the recently developed permutation matrix representation (PMR) framework. Our approach extends a…

Computational Physics · Physics 2026-01-27 Arman Babakhani , Lev Barash , Itay Hen

We propose a Hamiltonian for a nonrelativistic spin 1/2 \QTR{it}{free} particle (e.g. an electron) and find that it contains information of its internal degrees of freedom in the rest coordinate system. We comment on the dynamical symmetry…

Quantum Physics · Physics 2007-05-23 S. Bruce

We develop a computational method to learn a molecular Hamiltonian matrix from matrix-valued time series of the electron density. As we demonstrate for three small molecules, the resulting Hamiltonians can be used for electron density…

Computational Physics · Physics 2020-09-01 Harish S. Bhat , Karnamohit Ranka , Christine M. Isborn

An integrable Hamiltonian system presents monodromy if the action-angle variables cannot be defined globally. As a prototype of classical monodromy with azimuthal symmetry, we consider a linear molecule interacting with external fields and…

Mathematical Physics · Physics 2022-04-06 Juan J. Omiste , Rosario González-Férez , Rafael Ortega

We investigate the $S=2$ antiferromagnetic quantum spin chain with the exchange and single-ion anisotropies in a magnetic field, using the numerical exact diagonalization of finite-size clusters and the level spectroscopy analysis. It is…

Strongly Correlated Electrons · Physics 2019-08-09 Tôru Sakai , Kiyomi Okamoto , Takashi Tonegawa