### Magnetism and Structure in Systems of Reduced Dimension

Free download.
Book file PDF easily for everyone and every device.
You can download and read online Magnetism and Structure in Systems of Reduced Dimension file PDF Book only if you are registered here.
And also you can download or read online all Book PDF file that related with Magnetism and Structure in Systems of Reduced Dimension book.
Happy reading Magnetism and Structure in Systems of Reduced Dimension Bookeveryone.
Download file Free Book PDF Magnetism and Structure in Systems of Reduced Dimension at Complete PDF Library.
This Book have some digital formats such us :paperbook, ebook, kindle, epub, fb2 and another formats.
Here is The CompletePDF Book Library.
It's free to register here to get Book file PDF Magnetism and Structure in Systems of Reduced Dimension Pocket Guide.

Reed and E. Fawcett, Phys. Meservey, P. Tedrow and P. Fulde, Phys. Stearns, J. Julliere, Phys. CrossRef Google Scholar. Johnson and R. Silsbee, Phys. Baibich, J. Broto, A. Fert, F. Nguyen van Dau, F. Petroff, P. Etienne, G. Creuzet, A. Friederich and J. Chazeles, Phys. Pratt, Jr. Lee, J. Slaughter, R. LoLoee, P. Schroeder and J. Bass, Phys. Berkowitz, J. Mitchell, M. Carey, A. Young, S. Zhang, F. Spada, F. Parker, A. Hutton and G. Thomas, Phys. Xiao, J. Jiang and CL. Chien, Phys. Prinz 1 1. Personalised recommendations. Cite chapter How to cite?

ENW EndNote. On the theory of ferromagnetism. Bethe, H. Metal theory. Onsager, L. Crystal statistics I. A two-dimensional model with an order-disorder transition. Mermin, N. Absense of ferromagnetism or antiferromagnetism in one- or two-dimensional isotropic Heisenberg models. Berezinskii, V. Destruction of long-range order in one-dimensional and two-dimensional systems possessing a continuous symmetry group.

Quantum systems. JETP 34 , — Kosterlitz, J. Long range order and metastability in two dimensional solids and superfluids. Solid State Phys. Ordering, metastability and phase transitions in two-dimensional systems. Haldane, F.

Continuum dynamics of the 1-D Heisenberg anti-ferromagnet identification with the O 3 non-linear sigma-model. A 93 , — Giamarchi, T. Shastry, B. Exact ground state of quantum-mechanical antiferromagnet. B , — Miyahara, S.

## Magnetism and Structure in Systems of Reduced Dimension (Nato Science Series B:)

Kageyama, H. Exact dimer ground state and quantized magnetization plateaus in the two-dimensional spin system SrCu 2 BO 3 2. Direct evidence for the localized single-triplet excitations and the dispersive multitriplet excitations in SrCu 2 BO 3 2.

Takigawa, M. Matsuda, Y. Corboz, P. Crystals of bound states in the magnetization plateaus of the Shastry — Sutherland model. Koga, A. Zayed, M. Matsubara, T. A lattice model of liquid helium, I.

Nikuni, T. Bose—Einstein condensation of dilute magnons in TlCuCl 3. Waki, T. Jaime, M. Aczel, A.

## ISC - Magnetism in low dimensional systems

Samulon, E. Manaka, H. Field-induced magnetic long-range order in the ferromagnetic-antiferromagnetic alternating Heisenberg chain system CH 3 2 CHNH 3 CuCl 3 observed by specific heat measurements. Zapf, V. Bose—Einstein condensation in quantum magnets. Ordered magnetic phases of the frustrated spin-dimer compound Ba 3 Mn 2 O 8. B 77 , Lieb, E. Two soluble models of an antiferromagnetic chain. Bonner, J. Linear magnetic chains with anisotropic coupling. A , — Belik, A. Solid State Chem. Johannes, M. Sr 2 Cu PO 4 2 : a real material realization of the one-dimensional nearest neighbor Heisenberg chain.

B 74 , Excitation spectra of the linear alternating antiferromagnet. B 25 , — Johnston, D.

B 61 , — Kokado, S. Jpn 68 , — Borras-Almenar et al. Alternating chains with ferromagnetic and antiferromagnetic interactions. Theory Magn. He, Z. BaCu 2 V 2 O 8 : Quasi-one-dimensional alternating chain compound with a large spin gap. B 69 , Ghoshray, K.

### Research Highlights

B 71 , Koo, H. Salunke, S. Klyushina, E. B 93 , Nonlinear theory of large-spin Heisenberg antiferromagnets: semiclassically quantized solitons of the one-dimensional easy-axis Neel state. Botet, R. Ground state properties of a spin-1 antiferromagnetic chain.

B 27 , — Nightingale, M. Gap of the linear spin-1 Heisenberg antiferromagnet: a Monte Carlo calculation. B 33 , — Uchiyama, Y. Spin-vacancy-induced long-range order in a new Haldane-gap antiferromagnet. Zheludev, A. Magnetic excitations in coupled Haldane spin chains near the quantum critical point. B 62 , — Bray, J. Observation of a spin-Peierls transition in a Heisenberg antiferromagnetic linear-chain system. Hase, M. Bulaevskii, L. Spin — Peierls transition in magnetic field. Solid State Commun. Nishi, M. Neutron-scattering study on the spin-Peierls transition in a quasi-one-dimensional magnet CuGeO 3.

B 50 , — Northby, J. Field-dependent differential susceptibility studies on tetrathiafulvalene-AuS 4 C 4 CF 3 4 : Universal aspects of the spin-Peierls phase diagram. Magnetic phase diagram of the spin-Peierls cuprate CuGeO 3. B 48 , — Nojiri, H. Observation of magnetization saturation of CuGeO 3 in ultrahigh magnetic fields up to T. B 55 , — Isobe, M. Ohama, T. B 59 , — Sawa, H. X-ray anomalous scattering study of a charge-ordered state in NaV 2 O 5.

Ohwada, K. Redhammer, G. Acta Cryst. Konstantinovic, M. Silverstein, H. Direct measurement of the spin gap in a quasi-one-dimensional clinopyroxene: NaTiSi 2 O 6. B 90 , Hikihara, T. B 70 , Drechsler, S. Helimagnetism and weak ferromagnetism in edge-shared chain cuprates.

Lebernegg, S. B 95 , Law, J. Quasi-one-dimensional antiferromagnetisn and multiferroicity in CuCrO 4. B 84 , B 78 , Masuda, T. Competition between helimagnetism and commensurate quantum spin correlations in LiCu 2 O 2. Dutton, S. Quantum spin liquid in frustrated one-dimensional LiCuSbO 4. Magnetic and resonant properties of quasi-one-dimensional antiferromagnet LiCuVO 4.

B 64 , Enderle, M. Schrettle, F. Mourigal, M. Evidence of a bond-nematic phase in LiCuVO 4. Orlova, A. Nuclear magnetic resonance signature of the spin-nematic phase in LiCuVO 4 at high magnetic fields. Grafe, H. Signatures of a magnetic field-induced unconventional nematic liquid in the frustrated and anisotropic spin-chain cuprate LiCuSbO 4. The results clearly show the existence of dipolar magnetic ordering, which interestingly takes different forms depending on particle arrangement and magnetic history.

Far from being "weak", dipolar magnetism in low-dimensional nanoparticle structures reveals a tendency to survive major degrees of structural disorder in the arrangement of the nanoparticles, to the point that we envision the existence of amorphous meta-materials with ferromagnetic character.

## Magnetism and Structure in Systems of Reduced Dimension

For chains wider than 1 particle across, particles are typically assembled into triangular close-packed lattices, although square lattice arrangements are also occasionally seen. Phase contour spacing as in Fig. We applied off-axis electron holography 25 , 26 to map directly, and non-invasively, the projected magnetic field, B in-plane , of the elongated nanoparticle assemblies with a nominal spatial resolution of 6.

Chains wider than one particle show more complicated initial states. In a 3-particle-wide chain ii , ferromagnetic alignment is observed only for two of the three strands while antiferromagnetic alignment is found between these two strands and the third one. The antiferromagnetic alignment seems to be related to cases of square lattice arrangement between some of the particles. In a 6-particle-wide chain iii , several flux-closed regions with domain widths of up to 5 particles are observed in the initial state. No out-of-plane cores, typical for regular vortices in continuous thin films, are found as a result of the absence of inter-particle exchange interactions.

### Introduction

In order to quantify dipolar ferromagnetic order in the nanoparticle structures we examine a set of chains I—VII, Fig. The average number of nearest neighbour particles coordination number, CN of each particle ranges from 2 for the single-particle chain I to 5. From the projected field maps Fig. The thin green circular lines superimposed on b indicate the expected locations of the first few neighbouring peaks for a 2D close-packed lattice with a measured nearest neighbour distance d nn of As given in Fig.

This suggests that the geometric disorder may be driven primarily by the size distribution, and that the packing of the particles on the substrate is almost as dense as possible for the given particle size distribution. In order to simulate magnetic order in the chains, we used a computational framework based on an adaptation of the Landau-Lifshitz-Gilbert equations that describe semi-classically the dynamics of interacting magnetic moments inside materials Starting from the measured coordinates and radii of the particles, and assuming an initial in-plane alignment that mimics the external field applied to saturate the structures, we calculated the expected ground states upon removal of the field for particles with zero magnetic anisotropy.

Despite edge effects and a few minor discrepancies between simulations and observations, for example in the exact position of the vortex in chain IV, the simulations confirm magnetic ordering as being long-range dipolar ferromagnetic. We also simulated relaxation from an initial random distribution of moments, obtaining results similar to the initial magnetic states, with shorter range magnetic order that includes flux-closed regions that are a few particles in width for the chains wider than 1 particle.

In these cases, many degenerate magnetic states exist. This correspondence between simulated and observed states together with the presence of complex initial magnetic states suggest that the assembly into chains is not entirely magnetically driven. The simulations were used also to assess structures that were not available experimentally by artificially increasing the degree of geometrical lattice disorder for a finite lattice of dipoles by adding a random component to the position and size of each nanoparticle. Even in this extreme case, simulations of the magnetic saturation remanence show that M has decreased only from 0.

The persistent ferromagnetism in the quasi-2D structures appears contrary to the spin-glass behavior often expected in disordered nanoparticle-systems. Color-code as shown in Fig. In contrast, at remanence after saturation, overall dipolar ferromagnetic order is extremely persistent even in case of a non-triangular lattice. We interpret our results as supporting the existence of amorphous dipolar ferromagnets: i.

These observations are contrary to the magnetic glass behavior found in random 3D particle arrangements 13 , 17 , 18 , 19 and are of direct relevance for the use of quasi-2D nanoparticle assemblies in magnetic devices such as thin elongated memories, tunnel junctions, and sensors. The cobalt precursor solution 0. One drop of the cobalt nanoparticle solution was then deposited onto a holey carbon-coated copper TEM grid and left to dry inside a glove box.

Following this procedure, the different holograms were recorded with the chains magnetized in opposite directions. The mean inner potential was separated from the magnetic potential as described in [ 25 ].

- EPR of Free Radicals in Solids I: Trends in Methods and Applications.
- Magnetism in thin films.
- Ordered Mesoporous Materials;
- Magnetism and Structure in Systems of Reduced Dimension (Nato Science Series B:).
- StartupNation.
- The Hungry Ghosts;
- What is a first edition?.

The magnitude and orientation of each moment was measured by integrating the phase gradient components within each nanoparticle in each chain. The measurement is generally perturbed by the presence of neighboring particles proportionally to the magnitude and orientation of the field generated by surrounding particles. However, if the system is at equilibrium, no torque is acting on any of the moments so that the local field and each moment are aligned; as a consequence, we do not expect significant perturbations in the measured orientation.

The magnetic relaxation of the chains was simulated by an iterative approach based on a simplified version of the LLG equations, in which precession of moments around the local magnetic field was ignored high damping coefficient. A simulation proceeds in steps: 1 the simulated structure is created by assigning coordinates and diameters of the nanoparticles from an experimental micrograph; 2 each particle is assumed to be spherical, and with a magnetic moment proportional to its volume and with no magnetic anisotropy; 3 the initial orientation is chosen as either "saturated " where all moments are aligned with a small random component , or "random" where all moments are pointing randomly; 4 the local magnetic field acting on the i-th particle is calculated as superposition of the magnetic fields generated by the remaining N-1 particles; 5 the i-th moment is rotated towards the local field by an amount proportional to the torque, i.

All authors discussed the results. Europe PMC requires Javascript to function effectively. Recent Activity. The snippet could not be located in the article text. This may be because the snippet appears in a figure legend, contains special characters or spans different sections of the article. Sci Rep. Published online Feb 6. PMID: Beleggia , 3, 6 T. Kasama , 3 R. Harrison , 4 R. Dunin-Borkowski , 3, 5 V.

Puntes , 2 and C. Frandsen a, 1. Find articles by M.