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Plaquette valence-bond crystal in the frustrated Heisenberg quantum antiferromagnet on the square lattice

Related publications (31)

Frustrated magnets in the limit of infinite dimensions: Dynamics and disorder-free glass transition

We study the statistical mechanics and the equilibrium dynamics of a system of classical Heisenberg spins with frustrated interactions on a d -dimensional simple hypercubic lattice, in the limit of infinite dimensionality d -> infinity . In the analysis we ...

Amer Physical Soc2024

Structure, Spin Correlations, and Magnetism of the S=1/2 Square-Lattice Antiferromagnet Sr2CuTe1-xWxO6 (0 ≤ x ≤ 1)

Henrik Moodysson Rønnow, Peter Babkevich, Sami Juhani Vasala, Ellen Fogh

Quantum spin liquids are highly entangled magnetic states with exotic properties. The S = 1/2 square-lattice Heisenberg model is one of the foundational models in frustrated magnetism with a predicted, but never observed, quantum spin liquid state. Isostru ...

Amer Chemical Soc2023

Diffuse spin waves and classical spin liquid behavior in the kagome antiferromagnet chromium jarosite, KCr3(OD)6(SO4)2

Ivica Zivkovic, Sofie Janas

The dynamics of the S = 3/2 kagome antiferromagnet chromium jarosite, KCr3(OD)(6)(SO4)(2), was studied using high-resolution neutron time-of-flight spectroscopy on a polycrystalline sample with a nearly stoichiometric magnetic lattice [2.8(2)% Cr vacancies ...

Amer Physical Soc2023

Spin Textures in 2D Magnets

Lukas Powalla

The continuous reduction of the structural size in nanotechnology slowed down over the last decade, approaching the natural limit of single atoms as building blocks of matter. Therefore, intensive research is directed toward exploring new frontiers, in par ...

EPFL2023

Numerical investigation of bound states in quantum magnets

Mithilesh Nayak

Bound-states of particles are an interesting problem in quantum mechanics dating back to 1931 Bethe's solution of spin-1/2 Heisenberg chain. These exotic composite states are realized in quantum magnets and are detectable in inelastic neutron scattering (I ...

EPFL2023

Small-angle neutron scattering study of mesoscale magnetic disordering and skyrmion phase suppression in the frustrated chiral magnet Co6.75Zn6.75Mn6.51

Henrik Moodysson Rønnow, Jonathan White

Co-Zn-Mn chiral cubic magnets display versatile magnetic skyrmion phases, including equilibrium phases stable far above and far below room temperature, and the facile creation of robust far-from-equilibrium skyrmion states. In this system, compositional di ...

INT UNION CRYSTALLOGRAPHY2022

Tensor network investigation of frustrated Ising models

Jeanne Colbois

In spin systems, geometrical frustration describes the impossibility of minimizing simultaneously all the interactions in a Hamiltonian, often giving rise to macroscopic ground-state degeneracies and emergent low-temperature physics. In this thesis, combin ...

EPFL2022

Level crossings and chiral transitions in transverse-field Ising models of adatom and Rydberg chains

Ivo Aguiar Maceira

This thesis is motivated by recent experiments on systems described by extensions of the one-dimensional transverse-field Ising (TFI) model where (1) finite-size properties of Ising-ordered phases -- specifically, ground state level crossings -- were obser ...

EPFL2022

Spinon-like excitations in spin-1/2 quantum antiferromagnets

Irina Safiulina

Quantum magnetism remains a hot topic in condensed matter physics due to its complexity and possible powerful and significant applications in data storage and memory. To understand how the materials can achieve these goals, one should have a clear idea abo ...

EPFL2022

Pivotal Role of Intersite Hubbard Interactions in Fe-Doped alpha-MnO2

Iurii Timrov

We present a first-principles investigation of the structural, electronic, and magnetic properties of the pristine and Fe-doped alpha-MnO2 using density-functional theory with extended Hubbard functionals. The onsite U and intersite V Hubbard parameters ar ...

AMER CHEMICAL SOC2022

Crossover of high-energy spin fluctuations from collective triplons to localized magnetic excitations in Sr14-xCaxCu24O41 ladders

Henrik Moodysson Rønnow, Yi Tseng, Thorsten Schmitt

We studied the magnetic excitations in the quasi-one-dimensional (q-1D) ladder subsystem of Sr14-xCaxCu24O41 (SCCO) using Cu L-3-edge resonant inelastic X-ray scattering (RIXS). By comparing momentum-resolved RIXS spectra with high (x = 12.2) and without ( ...

NATURE PORTFOLIO2022

Thermal critical points from competing singlet formations in fully frustrated bilayer antiferromagnets

Frédéric Mila, Antoine Yves Dimitri Fache

We examine the ground-state phase diagram and thermal phase transitions in a plaquettized fully frustrated bilayer spin-1/2 Heisenberg model. Based on a combined analysis from sign-problem free quantum Monte Carlo simulations, perturbation theory, and free ...

AMER PHYSICAL SOC2022

Solving frustrated Ising models using tensor networks

Frédéric Mila, Jeanne Colbois

Motivated by the recent success of tensor networks to calculate the residual entropy of spin ice and kagome Ising models, we develop a general framework to study frustrated Ising models in terms of infinite tensor networks that can be contracted using stan ...

2021

Artificial out-of-plane Ising antiferromagnet on the kagome lattice with very small farther-neighbor couplings

Frédéric Mila, Jeanne Colbois, Xueqiao Wang

Despite their simple formulation, short-range classical antiferromagnetic Ising models on frustrated lattices give rise to exotic phases of matter, in particular, due to their macroscopic ground-state degeneracy. Recent experiments on artificial spin syste ...

2021

Broken-Symmetry Ground States of the Heisenberg Model on the Pyrochlore Lattice

Giuseppe Carleo, Ao Chen

The spin-1/2 Heisenberg model on the pyrochlore lattice is an iconic frustrated three-dimensional spin system with a rich phase diagram. Besides hosting several ordered phases, the model is debated to possess a spin-liquid ground state when only nearest-ne ...

American Physical Society2021

Universal Aspects of Metamagnetic Transitions in Frustrated Ising Chains

Nagabhushan Ganesh Hegde

The study of magnetic frustration has been interesting due to the variety of magnetic ordering observed at low temperatures. At these temperatures thermal fluctuations become redundant and quantum fluctuations play a significant role in the determining the ...

EPFL2021

Static and dynamic properties of non-collinear quantum antiferromagnets explored by neutron scattering

Luc Testa

This thesis is devoted to the investigation of static and dynamic properties of two different sets of quantum magnets with neutron scattering techniques and the help of linear spin wave theory. Both systems are copper-based with spin-1/2, which makes them ...

EPFL2021

Order and dynamics in Kagome like compound Cu2OSO4 and other quantum magnets

Virgile Yves Favre

This thesis presents results of studies of novel compounds modeling complex fundamental physics phenomena. Cu2OSO4 is a copper based magnetic Mott Insulator system, where spin half magnetic moments form a new type of lattice. These intrinsically quantum pi ...

EPFL2021

Structural characterization and magnetic properties of chromium jarosite KCr3(OD)(6)(SO4)(2)

Sofie Janas

Potassium chromium jarosite, KCr3(OH)(6)(SO4)(2) (Cr-jarosite), is considered a promising candidate to display spin liquid behavior due to the strong magnetic frustration imposed by the crystal structure. However, the ground state magnetic properties have ...

ROYAL SOC CHEMISTRY2020

Long-range magnetic ordering in Li2MnGeO4 and precursor short-range spin correlations

Irina Safiulina, Artem Korshunov

Long-range magnetic ordering and short-range spin correlations in layered noncentrosymmetric orthogermanate Li2MnGeO4 were studied by means of polarized and unpolarized neutron scattering. The combined Rietveld refinement of synchrotron and neutron powder ...

2020