Spin Hamiltonians in Magnets: Theories and Computations

The effective spin Hamiltonian method has drawn considerable attention for its power to explain and predict magnetic properties in various intriguing materials. In this review, we summarize different types of interactions between spins (hereafter, spin interactions, for short) that may be used in effective spin Hamiltonians as well as the various methods of computing the interaction parameters. A detailed discussion about the merits and possible pitfalls of each technique of computing interaction parameters is provided.

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Noncollinear Two-Component Quasirelativistic Description of Spin Interactions in Exchange-Coupled Systems. Mapping Generalized Broken-Symmetry States to Effective Spin Hamiltonians

Journal of Chemical Theory and Computation ◽

10.1021/acs.jctc.7b01067 ◽

2018 ◽

Vol 14 (3) ◽

pp. 1267-1276 ◽

Cited By ~ 2

Author(s):

Artur Wodyński ◽

Martin Kaupp

Keyword(s):

Coupled Systems ◽

Broken Symmetry ◽

Effective Spin ◽

Spin Hamiltonians ◽

Spin Interactions ◽

Two Component ◽

Systems Mapping

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Temperature-dependent magnetic properties of FePt: Effective spin Hamiltonian model

EPL (Europhysics Letters) ◽

10.1209/epl/i2004-10404-2 ◽

2005 ◽

Vol 69 (5) ◽

pp. 805-811 ◽

Cited By ~ 198

Author(s):

O. N Mryasov ◽

U Nowak ◽

K. Y Guslienko ◽

R. W Chantrell

Keyword(s):

Magnetic Properties ◽

Spin Hamiltonian ◽

Temperature Dependent ◽

Effective Spin ◽

Hamiltonian Model

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Structural diversity and magnetic properties of six ferrocenyl monocarboxylate Mn(ii), Ni(ii) and Co(ii) complexes with 1D aqua, carboxyl or dinuclear hydroxyl bridges

CrystEngComm ◽

10.1039/d1ce00189b ◽

2021 ◽

Author(s):

Misbha Rafiq Khan ◽

Xiaoge Niu ◽

Tianling Chen ◽

Yan Liu ◽

Zhongyi Liu ◽

...

Keyword(s):

Magnetic Properties ◽

Magnetic Coupling ◽

Structural Diversity ◽

Different Types ◽

Structure Diversity

Six ferrocenyl monocarboxylate Mn(ii), Ni(ii) and Co(ii) complexes with different types of magnetic coupling bridges were synthesized successfully. 1–6 display intriguing structure diversity and magnetic properties.

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Exact mapping between a laser network loss rate and the classical XY Hamiltonian by laser loss control

Nanophotonics ◽

10.1515/nanoph-2020-0137 ◽

2020 ◽

Vol 9 (13) ◽

pp. 4117-4126 ◽

Cited By ~ 1

Author(s):

Igor Gershenzon ◽

Geva Arwas ◽

Sagie Gadasi ◽

Chene Tradonsky ◽

Asher Friesem ◽

...

Keyword(s):

Degrees Of Freedom ◽

Loss Rate ◽

Oscillation Amplitude ◽

Xy Model ◽

Spin Hamiltonian ◽

Laser Oscillator ◽

Physical Systems ◽

Network State ◽

Spin Hamiltonians ◽

Loss Control

AbstractRecently, there has been growing interest in the utilization of physical systems as heuristic optimizers for classical spin Hamiltonians. A prominent approach employs gain-dissipative optical oscillator networks for this purpose. Unfortunately, these systems inherently suffer from an inexact mapping between the oscillator network loss rate and the spin Hamiltonian due to additional degrees of freedom present in the system such as oscillation amplitude. In this work, we theoretically analyze and experimentally demonstrate a scheme for the alleviation of this difficulty. The scheme involves control over the laser oscillator amplitude through modification of individual laser oscillator loss. We demonstrate this approach in a laser network classical XY model simulator based on a digital degenerate cavity laser. We prove that for each XY model energy minimum there corresponds a unique set of laser loss values that leads to a network state with identical oscillation amplitudes and to phase values that coincide with the XY model minimum. We experimentally demonstrate an eight fold improvement in the deviation from the minimal XY energy by employing our proposed solution scheme.

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Effective Hamiltonian for a half-filled asymmetric ionic Hubbard chain with alternating on-site interaction

International Journal of Modern Physics B ◽

10.1142/s0217979215502604 ◽

2016 ◽

Vol 30 (03) ◽

pp. 1550260 ◽

Cited By ~ 1

Author(s):

I. Grusha ◽

M. Menteshashvili ◽

G. I. Japaridze

Keyword(s):

Magnetic Field ◽

Nearest Neighbor ◽

Effective Hamiltonian ◽

Heisenberg Chain ◽

Spin Hamiltonian ◽

Effective Spin ◽

One Dimensional ◽

The One ◽

Strong Repulsion ◽

Ionic Hubbard Model

We derive an effective spin Hamiltonian for the one-dimensional half-filled asymmetric ionic Hubbard model (IHM) with alternating on-site interaction in the limit of strong repulsion. It is shown that the effective Hamiltonian is that of a spin S = 1/2 anisotropic XXZ Heisenberg chain with alternating next-nearest-neighbor (NNN) and three-spin couplings in the presence of a uniform and a staggered magnetic field.

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