Related papers: Cluster formation in quantum critical systems
The formation of massive stellar clusters in turbulent molecular clouds is investigated. We include artificial star formation and energy feedback of newly born stars. The obtained systems are not likely to survive. Case studies to determine…
Recent neutron scattering measurements indicate that NaFe$_{1-x}$Cu$_{x}$As forms an antiferromagnetic stripe phase near $x\approx 0.5$ in a Mott insulating state. This copper concentration is well in excess of that required for…
Effects of alloying on the electronic and magnetic properties of Mn$_{x}$Co$_{y}$ ($x+y$=$n$=2-5; $x$=0-$n$) and Mn$_2$Co$_{11}$ nanoalloy clusters are investigated using the density functional theory (DFT). Unlike the bulk alloy, the…
The presence of energy shells in metallic clusters and atomic nuclei leads to a peculiar relation between the number of particles N and the structure, and this leads to a strong correlation between the energy spectrum and N. An analysis of…
Polycrystalline samples of the isostructural alloys UNi1-xCoxSi2 (0 <= x <= 1) were studied by means of x-ray powder diffraction, magnetization, electrical resistivity and specific heat measurements, at temperatures down to 2 K and in…
We discuss the behavior of quantum and classical pairwise correlations in critical systems, with the quantumness of the correlations measured by the quantum discord. We analytically derive these correlations for general real density…
Quantum criticality describes the collective fluctuations of matter undergoing a second-order phase transition at zero temperature. It is being discussed in a number of strongly correlated electron systems. A prototype case occurs in the…
Magnetic and transport properties of Ge(1-x-y)Mn(x)Eu(y)Te crystals with chemical compositions 0.041 < x < 0.092 and 0.010 < y < 0.043 are studied. Ferromagnetic order is observed at 150 < T < 160 K. Aggregation of magnetic ions into…
With a surge of interest in spintronics, the manipulation and detection of colossal magnetoresistance in quasi-two-dimensional layered magnetic materials have become a key focus, driven by their relatively scarce occurrence compared to…
We investigate a generalized antiferromagnetic cluster XY model in a transverse magnetic field, where long-range interactions decay algebraically with distance. This model can be exactly solvable within a free fermion framework. By…
In a Newtonian system with localized interactions the whole set of particles is naturally decomposed into dynamical clusters, defined as finite groups of particles having an influence on each other's trajectory during a given interval of…
Magnetic fluctuations near to quantum criticality can have profound effects. They lead to characteristic scaling at high temperature which may ultimately give way to a reconstruction of the phase diagram and the formation of new phases at…
The understanding of clustering aspects at the ground state of nuclei and in fast rotating ones within the framework of covariant density functional theory has been reviewed and reanalyzed. The appearance of many exotic nuclear shapes in…
We study a Hamiltonian system describing a three-spin-1/2 cluster-like interaction competing with an Ising-like anti-ferromagnetic interaction. We compute free energy, spin correlation functions and entanglement both in the ground and in…
We demonstrate how exchange hardening can arise in a chemically-disordered solid solution from a first-principles statistical mechanics approach. A general mixed-basis chemical and magnetic cluster expansion has been developed, and applied…
In this thesis, we study the novel dynamic critical phenomena induced by superfluidity and the chiral magnetic effect in Quantum Chromodynamics (QCD), respectively. In particular, we find the new dynamic universality class of the…
Inelastic neutron scattering experiments performed on a single crystal of the antiferromagnetic compound Ce$_{0.87}$La$_{0.13}$Ru$_{2}$Si$_{2}$ under applied pressures of up to 5 kbar are reported. A quantum critical point is reached at…
In recent years, a better understanding of the Monte Carlo method has provided us with many new techniques in different areas of statistical physics. Of particular interest are so called cluster methods, which exploit the considerable…
We present evidence for the existence of magnetic clusters of approximately 20 \AA in the strongly correlated alloy system CeNi$_{1-x}$Cu$_{x}$ (0.7 $\le$ x $\le$ 0.2) based on small angle neutron scattering experiments as well as the…
Calculations of the electronic and magnetic properties of the non-magnetic metallic compound YFe$_2$Si$_2$ are reported. These show that at the density functional level a magnetic state involving ordering along the $c$-axis. The electronic…