相关论文: Magnetic dipolar ordering and relaxation in the hi…
We report the first example of a transition to long-range magnetic order in a purely dipolarly interacting molecular magnet. For the magnetic cluster compound Mn6O4Br4(Et2dbm)6, the anisotropy experienced by the total spin S=12 of each…
Dipolar coupling in crystals of the Mn$_{12}$Ac molecular magnet elongated along the anisotropy axis favors ferromagnetic ordering below the mean-field Curie temperature 0.71 K. With the help of Monte Carlo on crystals of up to one million…
We report on the Fe17 high-spin molecular cluster and show that this system is an exemplification of nanostructured dipolar magnetism. Each Fe17 molecule, with spin S=35/2 and axial anisotropy as small as D=-0.02K, is the magnetic unit that…
At temperatures below the magnetic anisotropy energy, monodomain magnetic systems (small particles, nanomagnetic devices, etc.) must relax quantum mechanically. This quantum relaxation must be mediated by the coupling to both nuclear spins…
We report on a 59Co NMR investigation of the trigonal cobaltate Ca3Co2O6 carried out on a single crystal, providing precise determinations of the electric field gradient and chemical shift tensors, and of the internal magnetic fields at the…
We study the magnetic relaxation of a system of localized spins interacting through weak dipole interactions, at a temperature large with respect to the ordering temperature but low with respect to the crystal field level splitting. The…
Among the 3d transition metal ions doped polar Ni3TeO6, Mn-doped Ni3TeO6 has stimulated great interest due to its high magnetic ordering temperature and complex magnetic phases, but the mechanism of magnetoelectric (ME) coupling is far from…
We have synthesized single crystals of Na$_3$Co$_2$SbO$_6$ and characterized the structure and magnetic order by measuring anisotropic magnetic properties, heat capacity, x-ray and neutron single crystal diffraction. Magnetic properties and…
We show that the low-temperature physics of molecular nanomagnets, contrary to the prevailing one-molecule picture, must be determined by the long-range magnetic ordering due to many-body dipolar interactions. The calculations here…
This thesis contains a thorough investigation of the quantum spin dynamics in Mn12-ac and Mn6 Single-molecule magnets. In particular, we have investigated the interplay between quantum tunneling of magnetization and nuclear spin dynamics in…
We report temperature (T) dependence of dc magnetization, electrical resistivity (rho(T)), and heat-capacity of rare-earth (R) compounds, Gd3RuSn6 and Tb3RuSn6, which are found to crystallize in the Yb3CoSn6-type orthorhombic structure…
We use neutron diffraction to probe the magnetization components of a crystal of Mn12 single-molecule magnets. Each of these molecules behaves, at low temperatures, as a nanomagnet with spin S = 10 and strong anisotropy along the…
Modeling blocking temperature in molecular magnets has been a long standing problem in the field of molecular magnetism. We investigate this problem using a kinetic Monte Carlo (kMC) approach on an assembly of 100,000 short molecular…
We derive a simple system of equations to describe the magnetization relaxation of a molecular spin in weak interaction with a thermal bath for the whole temperature domain. Using this for the intermediate temperature domain where the…
The dielectric behavior of the single crystals of the spin-chain system Ca3Co2O6, undergoing geometrically frustrated antiferromagnetic ordering below 25 K, has been investigated as a function of temperature and magnetic field (H) and…
The results of ac and dc magnetization and heat capacity measurements as a function of temperature (T = 1.8 to 300 K) are reported for a quasi-one-dimensional compound, Ca$_3$CuMnO$_6$, crystallizing in a triclinically distorted…
We have measured and calculated the magnetocaloric effect in macroscopic samples of oriented high-spin molecular clusters like Mn12 and Fe8 as a function of the temperature and both the intensity and the sweeping rate of the applied…
Nuclear magnetism in n-doped semiconductors with positive hyperfine constant is revisited. Two kinds of nuclear magnetic ordering can be induced by resident electrons in a deeply cooled nuclear spin system. At positive nuclear spin…
The dependence of the magnetic susceptibility on the magnetic field is investigated for the single molecular magnet [Mn(hfac)$_2$NITPh]$_6$. The spikes of the susceptibility detected in a magnetic field ranging from 90 T to 285 T are…
The low-temperature antiferromagnetic state of the Sm-ions in both nonsuperconducting SmFeAsO and superconducting SmFeAsO$_{0.9}$F$_{0.1}$ single crystals was studied by magnetic torque, magnetization, and magnetoresistance measurements in…