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Alfonso-Moro M, Guisset V, David P, Canals B, Coraux J, Rougemaille N. Geometrical Frustration, Correlated Disorder, and Emerging Order in a Corrugated C_{60} Monolayer. Phys Rev Lett 2023; 131:186201. [PMID: 37977638 DOI: 10.1103/physrevlett.131.186201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 01/31/2023] [Accepted: 09/13/2023] [Indexed: 11/19/2023]
Abstract
Under certain experimental conditions, the deposition of C_{60} molecules onto an atomically flat copper surface gives rise to the formation of corrugated islands. This corrugation, which reflects a molecular displacement perpendicular to the surface plane, presents an astonishing pattern: It is well described by a frustrated Ising spin Hamiltonian whose thermodynamics is compatible with a spin liquid about to transit toward an ordered zigzag state. Here we study the statistical properties of such a molecular corrugation using a structure factor analysis, a tool generally employed in frustrated magnetism. More specifically, the real and reciprocal space analysis of pairwise molecule correlations allows us to demonstrate that the C_{60}/Cu system, in which magnetism is totally absent, has all the characteristics of a triangular Ising antiferromagnet. Our results indicate that the organization of two-dimensional matter, at the molecular length scale, sometimes turns out to be particularly close to that encountered in highly frustrated magnets.
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Affiliation(s)
- M Alfonso-Moro
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - V Guisset
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - P David
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - B Canals
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - J Coraux
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - N Rougemaille
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
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2
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King AD, Coraux J, Canals B, Rougemaille N. Magnetic Arctic Circle in a Square Ice Qubit Lattice. Phys Rev Lett 2023; 131:166701. [PMID: 37925737 DOI: 10.1103/physrevlett.131.166701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 09/15/2023] [Indexed: 11/07/2023]
Abstract
Under certain boundary conditions, the square ice model exhibits a phase separation in which the core of the system is disordered while its outer region remains ordered. This phenomenon, known as the "arctic circle," has been studied theoretically in combinatorial mathematics and statistical mechanics. Here, we realize the physics of the arctic circle experimentally for the first time, using a programmable lattice of superconducting qubits, and investigate its properties under the prism of a highly frustrated magnet. Our work reveals two unexpected properties. First, the disordered spin manifold confined within the arctic curve is a spin liquid whose average spin texture resembles that of an antivortex, i.e., it is a topologically charged Coulomb phase. Second, monopole quasiparticle excitations, which are totally absent in theoretical works, can be isolated in a phase-separated system. Remarkably, a monopole segregation mechanism is observed, in which the monopoles are sorted according to the magnetic charge and magnetic moment they carry, without the application of an external driving force.
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Affiliation(s)
- A D King
- D-Wave Systems, Burnaby, British Columbia V5G 4M9, Canada
| | - J Coraux
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - B Canals
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
| | - N Rougemaille
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut Néel, Grenoble 38000, France
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3
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Schánilec V, Brunn O, Horáček M, Krátký S, Meluzín P, Šikola T, Canals B, Rougemaille N. Approaching the Topological Low-Energy Physics of the F Model in a Two-Dimensional Magnetic Lattice. Phys Rev Lett 2022; 129:027202. [PMID: 35867462 DOI: 10.1103/physrevlett.129.027202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/11/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
We demonstrate that the physics of the F model can be approached very closely in a two-dimensional artificial magnetic system. Faraday lines spanning across the lattice and carrying a net polarization, together with chiral Faraday loops characterized by a zero magnetic susceptibility, are imaged in real space using magnetic force microscopy. Our measurements reveal the proliferation of Faraday lines and Faraday loops as the system is brought from low- to high-energy magnetic configurations. They also reveal a link between the Faraday loop density and icelike spin-spin correlations in the magnetic structure factor. Key for this Letter, the density of topological defects remains small, on the order of 1% or less, and negligible compared to the density of Faraday loops. This is made possible by replacing the spin degree of freedom used in conventional lattices of interacting nanomagnets by a micromagnetic knob, which can be finely tuned to adjust the vertex energy directly, rather than modifying the two-body interactions.
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Affiliation(s)
- V Schánilec
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
| | - O Brunn
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
- Institute of Scientific Instruments of the Czech Academy of Sciences, Královopolská 147, 612 64 Brno, Czech Republic
- Institute of Physical Engineering, Brno University of Technology, Technická 2, 616 69 Brno, Czech Republic
| | - M Horáček
- Institute of Scientific Instruments of the Czech Academy of Sciences, Královopolská 147, 612 64 Brno, Czech Republic
| | - S Krátký
- Institute of Scientific Instruments of the Czech Academy of Sciences, Královopolská 147, 612 64 Brno, Czech Republic
| | - P Meluzín
- Institute of Scientific Instruments of the Czech Academy of Sciences, Královopolská 147, 612 64 Brno, Czech Republic
| | - T Šikola
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
- Institute of Physical Engineering, Brno University of Technology, Technická 2, 616 69 Brno, Czech Republic
| | - B Canals
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
| | - N Rougemaille
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
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4
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Schánilec V, Canals B, Uhlíř V, Flajšman L, Sadílek J, Šikola T, Rougemaille N. Bypassing Dynamical Freezing in Artificial Kagome Ice. Phys Rev Lett 2020; 125:057203. [PMID: 32794868 DOI: 10.1103/physrevlett.125.057203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 07/01/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
Spin liquids are correlated, disordered states of matter that fluctuate even at low temperatures. Experimentally, the extensive degeneracy characterizing their low-energy manifold is expected to be lifted, for example, because of dipolar interactions, leading to an ordered ground state at absolute zero. However, this is not what is usually observed, and many systems, whether they are chemically synthesized or nanofabricated, dynamically freeze before magnetic ordering sets in. In artificial realizations of highly frustrated magnets, ground state configurations, and even low-energy manifolds, thus remain out of reach for practical reasons. Here, we show how dynamical freezing can be bypassed in an artificial kagome ice. We illustrate the efficiency of our method by demonstrating that the a priori dynamically inaccessible ordered ground state and fragmented spin liquid configurations can be obtained reproducibly, imaged in real space at room temperature, and studied conveniently. We then identify the mechanism by which dynamical freezing occurs in the dipolar kagome ice.
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Affiliation(s)
- V Schánilec
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
| | - B Canals
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
| | - V Uhlíř
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
| | - L Flajšman
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
| | - J Sadílek
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
| | - T Šikola
- Central European Institute of Technology, CEITEC BUT, Brno University of Technology, Purkyňova 123, Brno 612 00, Czech Republic
- Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2, Brno, 616 69, Czech Republic
| | - N Rougemaille
- Univ. Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL, 38000 Grenoble, France
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5
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Grenier B, Petit S, Simonet V, Canévet E, Regnault LP, Raymond S, Canals B, Berthier C, Lejay P. Longitudinal and transverse Zeeman ladders in the Ising-like chain antiferromagnet BaCo(2)V(2)O(8). Phys Rev Lett 2015; 114:017201. [PMID: 25615498 DOI: 10.1103/physrevlett.114.017201] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Indexed: 06/04/2023]
Abstract
We explore the spin dynamics emerging from the Néel phase of the chain compound antiferromagnet BaCo(2)V(2)O(8). Our inelastic neutron scattering study reveals unconventional discrete spin excitations, so-called Zeeman ladders, understood in terms of spinon confinement, due to the interchain attractive linear potential. These excitations consist of two interlaced series of modes, respectively, with transverse and longitudinal polarization. The latter, which correspond to a longitudinal fluctuation of the ordered moment, have no classical counterpart and are related to the zero-point fluctuations that weaken the ordered moment in weakly coupled quantum chains. Our analysis reveals that BaCo(2)V(2)O(8), with moderate Ising anisotropy and sizable interchain interactions, remarkably fulfills the conditions necessary for the observation of discrete long-lived longitudinal excitations.
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Affiliation(s)
- B Grenier
- Université Grenoble Alpes, INAC-SPSMS, F-38000 Grenoble, France and CEA, INAC-SPSMS, F-38000 Grenoble, France
| | - S Petit
- Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, F-91191 Gif-sur-Yvette, France
| | - V Simonet
- CNRS, Institut Néel, F-38042 Grenoble, France and Université Grenoble Alpes, Institut Néel, F-38042 Grenoble, France
| | - E Canévet
- Institut Laue-Langevin, CS 20156, F-38042 Grenoble Cedex 9, France
| | - L-P Regnault
- Université Grenoble Alpes, INAC-SPSMS, F-38000 Grenoble, France and CEA, INAC-SPSMS, F-38000 Grenoble, France
| | - S Raymond
- Université Grenoble Alpes, INAC-SPSMS, F-38000 Grenoble, France and CEA, INAC-SPSMS, F-38000 Grenoble, France
| | - B Canals
- CNRS, Institut Néel, F-38042 Grenoble, France and Université Grenoble Alpes, Institut Néel, F-38042 Grenoble, France
| | - C Berthier
- Université Grenoble Alpes, Laboratoire National des Champs Magnétiques Intenses, F-38000 Grenoble, France and CNRS, Laboratoire National des Champs Magnétiques Intenses, F-38000 Grenoble, France
| | - P Lejay
- CNRS, Institut Néel, F-38042 Grenoble, France and Université Grenoble Alpes, Institut Néel, F-38042 Grenoble, France
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Montaigne F, Lacour D, Chioar IA, Rougemaille N, Louis D, Mc Murtry S, Riahi H, Burgos BS, Menteş TO, Locatelli A, Canals B, Hehn M. Size distribution of magnetic charge domains in thermally activated but out-of-equilibrium artificial spin ice. Sci Rep 2014; 4:5702. [PMID: 25029620 PMCID: PMC4100542 DOI: 10.1038/srep05702] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/26/2014] [Indexed: 11/09/2022] Open
Abstract
A crystal of emerging magnetic charges is expected in the phase diagram of the dipolar kagomé spin ice. An observation of charge crystallites in thermally demagnetized artificial spin ice arrays has been recently reported by S. Zhang and coworkers and explained through the thermodynamics of the system as it approaches a charge-ordered state. Following a similar approach, we have generated a partial order of magnetic charges in an artificial kagomé spin ice lattice made out of ferrimagnetic material having a Curie temperature of 475 K. A statistical study of the size of the charge domains reveals an unconventional sawtooth distribution. This distribution is in disagreement with the predictions of the thermodynamic model and is shown to be a signature of the kinetic process governing the remagnetization.
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Affiliation(s)
- F Montaigne
- Institut Jean Lamour, Université de Lorraine and CNRS, Vandoeuvre lès Nancy, F-54506, France
| | - D Lacour
- Institut Jean Lamour, Université de Lorraine and CNRS, Vandoeuvre lès Nancy, F-54506, France
| | - I A Chioar
- 1] CNRS, Institut NEEL, F-38042 Grenoble, France [2] Univ. Grenoble Alpes, Institut NEEL, F-38042 Grenoble, France
| | - N Rougemaille
- 1] CNRS, Institut NEEL, F-38042 Grenoble, France [2] Univ. Grenoble Alpes, Institut NEEL, F-38042 Grenoble, France
| | - D Louis
- Institut Jean Lamour, Université de Lorraine and CNRS, Vandoeuvre lès Nancy, F-54506, France
| | - S Mc Murtry
- Institut Jean Lamour, Université de Lorraine and CNRS, Vandoeuvre lès Nancy, F-54506, France
| | - H Riahi
- Institut Jean Lamour, Université de Lorraine and CNRS, Vandoeuvre lès Nancy, F-54506, France
| | - B Santos Burgos
- Elettra-Sincrotrone Trieste S.C.p.A. S.S. 14 - km 163,5 in AREA Science Park, 34149 Basovizza, Trieste, Italy
| | - T O Menteş
- Elettra-Sincrotrone Trieste S.C.p.A. S.S. 14 - km 163,5 in AREA Science Park, 34149 Basovizza, Trieste, Italy
| | - A Locatelli
- Elettra-Sincrotrone Trieste S.C.p.A. S.S. 14 - km 163,5 in AREA Science Park, 34149 Basovizza, Trieste, Italy
| | - B Canals
- 1] CNRS, Institut NEEL, F-38042 Grenoble, France [2] Univ. Grenoble Alpes, Institut NEEL, F-38042 Grenoble, France
| | - M Hehn
- Institut Jean Lamour, Université de Lorraine and CNRS, Vandoeuvre lès Nancy, F-54506, France
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Riahi H, Montaigne F, Rougemaille N, Canals B, Lacour D, Hehn M. Energy levels of interacting curved nanomagnets in a frustrated geometry: increasing accuracy when using finite difference methods. J Phys Condens Matter 2013; 25:296001. [PMID: 23803392 DOI: 10.1088/0953-8984/25/29/296001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The accuracy of finite difference methods is related to the mesh choice and cell size. Concerning the micromagnetism of nano-objects, we show here that discretization issues can drastically affect the symmetry of the problem and therefore the resulting computed properties of lattices of interacting curved nanomagnets. In this paper, we detail these effects for the multi-axis kagome lattice. Using the OOMMF finite difference method, we propose an alternative way of discretizing the nanomagnet shape via a variable moment per cell scheme. This method is shown to be efficient in reducing discretization effects.
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Affiliation(s)
- H Riahi
- Institut Jean Lamour, CNRS-Université de Lorraine, boulevard des aiguillettes, BP 70239, F-54506 Vandoeuvre lès Nancy, France
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8
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Chaix L, de Brion S, Lévy-Bertrand F, Simonet V, Ballou R, Canals B, Lejay P, Brubach JB, Creff G, Willaert F, Roy P, Cano A. THz magnetoelectric atomic rotations in the chiral compound Ba3NbFe3Si2O14. Phys Rev Lett 2013; 110:157208. [PMID: 25167309 DOI: 10.1103/physrevlett.110.157208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 02/20/2013] [Indexed: 06/03/2023]
Abstract
We have determined the terahertz spectrum of the chiral langasite Ba3NbFe3Si2O14 by means of synchrotron-radiation measurements. Two excitations are revealed that are shown to have a different nature. The first one, purely magnetic, is observed at low temperature in the magnetically ordered phase and is assigned to a magnon. The second one persists far into the paramagnetic phase and exhibits both an electric and a magnetic activity at slightly different energies. This magnetoelectric excitation is interpreted in terms of atomic rotations and requires a helical electric polarization.
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Affiliation(s)
- L Chaix
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - S de Brion
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - F Lévy-Bertrand
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - V Simonet
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - R Ballou
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - B Canals
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - P Lejay
- Institut Néel, CNRS et Université Joseph Fourier, BP166, F-38042 Grenoble Cedex 9, France
| | - J B Brubach
- Synchrotron SOLEIL, L'Orme des Merisiers Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - G Creff
- Synchrotron SOLEIL, L'Orme des Merisiers Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - F Willaert
- Synchrotron SOLEIL, L'Orme des Merisiers Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - P Roy
- Synchrotron SOLEIL, L'Orme des Merisiers Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - A Cano
- European Synchrotron Radiation Facility, 6 rue Jules Horowitz, BP 220, 38043 Grenoble, France
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9
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Canals B, Schober H. Introduction to group theory. EPJ Web of Conferences 2012. [DOI: 10.1051/epjconf/20122200004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lhotel E, Simonet V, Ortloff J, Canals B, Paulsen C, Suard E, Hansen T, Price DJ, Wood PT, Powell AK, Ballou R. Domain-wall spin dynamics in kagome antiferromagnets. Phys Rev Lett 2011; 107:257205. [PMID: 22243109 DOI: 10.1103/physrevlett.107.257205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Indexed: 05/31/2023]
Abstract
We report magnetization and neutron scattering measurements down to 60 mK on a new family of Fe based kagome antiferromagnets, in which a strong local spin anisotropy combined with a low exchange path network connectivity lead to domain walls intersecting the kagome planes through strings of free spins. These produce unfamiliar slow spin dynamics in the ordered phase, evolving from exchange-released spin flips towards a cooperative behavior on decreasing the temperature, probably due to the onset of long-range dipolar interaction. A domain structure of independent magnetic grains is obtained that could be generic to other frustrated magnets.
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Affiliation(s)
- E Lhotel
- Institut Néel, CNRS & Université Joseph Fourier, BP 166, 38042 Grenoble Cedex 9, France.
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Rougemaille N, Montaigne F, Canals B, Duluard A, Lacour D, Hehn M, Belkhou R, Fruchart O, El Moussaoui S, Bendounan A, Maccherozzi F. Artificial kagome arrays of nanomagnets: a frozen dipolar spin ice. Phys Rev Lett 2011; 106:057209. [PMID: 21405433 DOI: 10.1103/physrevlett.106.057209] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 12/10/2010] [Indexed: 05/30/2023]
Abstract
Magnetic frustration effects in artificial kagome arrays of nanomagnets are investigated using x-ray photoemission electron microscopy and Monte Carlo simulations. Spin configurations of demagnetized networks reveal unambiguous signatures of long range, dipolar interaction between the nanomagnets. As soon as the system enters the spin ice manifold, the kagome dipolar spin ice model captures the observed physics, while the short range kagome spin ice model fails.
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Affiliation(s)
- N Rougemaille
- Institut Néel, CNRS-UJF, BP 166, 38042 Grenoble Cedex 9, France
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12
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Ressouche E, Simonet V, Canals B, Gospodinov M, Skumryev V. Magnetic frustration in an iron-based Cairo pentagonal lattice. Phys Rev Lett 2009; 103:267204. [PMID: 20366341 DOI: 10.1103/physrevlett.103.267204] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Indexed: 05/29/2023]
Abstract
The Fe3+ lattice in the Bi2Fe4O9 compound is found to materialize the first analogue of a magnetic pentagonal lattice. Because of its odd number of bonds per elemental brick, this lattice, subject to first neighbor antiferromagnetic interactions, is prone to geometric frustration. The Bi2Fe4O9 magnetic properties have been investigated by macroscopic magnetic measurements and neutron diffraction. The observed noncollinear magnetic arrangement is related to the one stabilized on a perfect tiling as obtained from a mean field analysis with direct space magnetic configuration calculations. The peculiarity of this structure arises from the complex connectivity of the pentagonal lattice, a novel feature compared to the well-known case of triangle-based lattices.
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Affiliation(s)
- E Ressouche
- CEA/Grenoble, INAC/SPSMS-MDN, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France.
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Robert J, Canals B, Simonet V, Ballou R. Propagation and ghosts in the classical kagome antiferromagnet. Phys Rev Lett 2008; 101:117207. [PMID: 18851328 DOI: 10.1103/physrevlett.101.117207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Indexed: 05/26/2023]
Abstract
We investigate the classical spin dynamics of the kagome antiferromagnet by combining Monte Carlo and spin dynamics simulations. We show that this model has two distinct low temperature dynamical regimes, both sustaining propagative modes. The expected gauge invariance type of the low energy, low temperature, out-of-plane excitations is also evidenced in the nonlinear regime. A detailed analysis of the excitations allows us to identify ghosts in the dynamical structure factor, i.e., propagating excitations with a strongly reduced spectral weight. We argue that these dynamical extinction rules are of geometrical origin.
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Affiliation(s)
- J Robert
- Laboratoire Léon Brillouin, CEA-CNRS, CEA-Saclay, 91191 Gif-sur-Yvette, France
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15
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Simonet V, Ballou R, Robert J, Canals B, Hippert F, Bordet P, Lejay P, Fouquet P, Ollivier J, Braithwaite D. Hidden magnetic frustration by quantum relaxation in anisotropic Nd langasite. Phys Rev Lett 2008; 100:237204. [PMID: 18643541 DOI: 10.1103/physrevlett.100.237204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Indexed: 05/26/2023]
Abstract
The static and dynamic magnetic properties of the Nd(3)Ga(5)SiO(14) compound, which appears as the first materialization of a rare-earth kagome-type lattice, were reexamined, owing to contradictory results in the previous studies. Neutron scattering, magnetization, and specific heat measurements were performed and analyzed, in particular, by fully taking account of the crystal electric field effects on the Nd(3+) ions. One of the novel findings is that the peculiar temperature independent spin dynamics observed below 10 K expresses single-ion quantum processes. This would short-circuit the frustration induced cooperative dynamics, which would emerge only at very low temperature.
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Affiliation(s)
- V Simonet
- Institut Néel, CNRS/UJF, BP 166, Grenoble Cedex 9, France
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16
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Robert J, Simonet V, Canals B, Ballou R, Bordet P, Lejay P, Stunault A. Spin-liquid correlations in the Nd-langasite anisotropic kagomé antiferromagnet. Phys Rev Lett 2006; 96:197205. [PMID: 16803138 DOI: 10.1103/physrevlett.96.197205] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2006] [Indexed: 05/10/2023]
Abstract
Dynamical magnetic correlations in the geometrically frustrated Nd(3)Ga(5)SiO(14) compound were probed by inelastic neutron scattering on a single crystal. A scattering signal with a ring shape distribution in reciprocal space and unprecedented dispersive features was discovered. Comparison with calculated static magnetic scattering from models of correlated spins suggests that the observed phase is a spin liquid inherent to an antiferromagnetic kagomé-like lattice of anisotropic Nd moments.
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Affiliation(s)
- J Robert
- Laboratoire Louis Néel, CNRS, Grenoble, France
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Lacroix C, Canals B, Núñez-Regueiro MD. Kondo Screening and Magnetic Ordering in Frustrated UNi4B. Phys Rev Lett 1996; 77:5126-5129. [PMID: 10062720 DOI: 10.1103/physrevlett.77.5126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Núñez-Regueiro MD, Lacroix C, Canals B. RCuO2.66 delafossites: A dilute s=1/2 kagomé-like lattice. Phys Rev B Condens Matter 1996; 54:R736-R739. [PMID: 9985422 DOI: 10.1103/physrevb.54.r736] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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