Related papers: Magnetic Cluster Excitations
Strongly interacting many-body systems exhibit collective properties that emerge from complex correlations among microscopic degrees of freedom. These cooperative phenomena govern the non-equilibrium response of quantum systems, with…
The magnetic properties of the molecular cluster Mn12Ac are due to the four Mn3+ ions which have spins S=3/2 and the eight Mn4+ ions with spins S=2. These spins are coupled by superexchange mechanism. We determine the four exchange…
In this paper we report results for magnetic observables of finite spin clusters composed of S=1/2 ions. We consider clusters of two, three and four spins in distinct spatial arrangements, with isotropic Heisenberg interactions of various…
Spectroscopic measurements with low-temperature scanning tunneling microscopes have been used very successfully for studying not only individual atomic or molecular spins on surfaces but also complexly designed coupled systems. The symmetry…
The advent of milli-kelvin scanning tunneling microscopes (STM) with inbuilt magnetic fields has opened access to the study of magnetic phenomena with atomic resolution at surfaces. In the case of single atoms adsorbed on a surface, the…
We study the dynamics of a suspension of magnetic nanoparticles. Their relaxation times are strongly size-dependent. The dominant mode of relaxation is also governed by the size of the particles. As a result the dynamics is greatly altered…
Spin states of two-dimensional Wigner clusters are considered at low temperatures, when all electrons are in ground coordinate states. The spin subsystem behavior is determined by antiferromagnetic exchange integrals. The spin states in…
Clustered quantum materials provide a new platform for the experimental study of many-body entanglement. Here we address a simple model of a single-molecule nano-magnet featuring N interacting spins in a transverse field. The field can…
How does magnetism behave when the physical dimension is reduced to the size of nanostructures? The multiplicity of magnetic states in these systems can be very rich, in that their properties depend on the atomic species, the cluster size,…
We report an unusual evolution of structure and magnetism in stoichiometric MnO clusters based on an extensive and unbiased search through the potential energy surface within density functional theory. The smaller clusters, containing up to…
We numerically study the magnetization of small metallic clusters. The magnetic susceptibility is enhanced for lower electronic densities due to the stronger influence of electron-electron interactions. The magnetic susceptibility…
NH4CuCl3 has two magnetization plateaus at one-quarter and three-quarters of the saturation magnetization, irrespective of the external field direction. Magnetic excitations in NH4CuCl3 have been investigated by means of neutron inelastic…
We present recent theoretical investigations on the dynamics of metal clusters in contact with an environment, deposited of embedded. This concerns soft deposition as well as irradiation of the deposited/embedded clusters by intense laser…
In this work, the many-spin interactions taking place in Mn12 large-spin clusters are extensively studied using the 8-spin model Hamiltonian, for which we determine the possible parameters based on experimental data. Account of the…
We study the formation of magnetic clusters in frustrated magnets in their cooperative paramagnetic regime. For this purpose, we consider the $J_1$-$J_2$-$J_3$ classical Heisenberg model on kagome and pyrochlore lattices with $J_2 = J_3=J$.…
Cosmology, high-energy physics and astrophysics are converging on the study of large-scale magnetic fields. While the experimental evidence for the existence of large-scale magnetization in galaxies, clusters and superclusters is rather…
The investigation of the dynamics of quantum many-body systems is a concerted effort involving computational studies of mathematical models and experimental studies of material samples. Some commonalities of the two tracks of investigation…
Here we follow, both experimentally and theoretically, the development of magnetism in Tb clusters from the atomic limit, adding one atom at a time. The exchange interaction is, surprisingly, observed to drastically increase compared to…
High energy resolution spectroscopic studies of quantum magnets have proven to be extremely valuable in directly accessing magnetodynamics quantities, such as energy barriers, magnetic interactions, lifetime of excited states and…
It is assumed that in a two-dimensional electron system with strong correlation (a Wigner liquid), appearance of some relatively slow-moving objects (clusters) composed of small number of electrons is possible. Such clusters may exist in…