Abstract Diluted axion star, a self-gravitating object with the quantum pressure balancing gravity, has been predicted in many models QCD or axion-like particle. It can be formed early universe and composes sizable fraction of dark matter. One could detect transient radio signals when it passes by magnetar particle converted into photon magnetic field. Using both numerical semi-analytic approac...

It is shown that, contrary to recent suggestions, the exponent ν, characterizing self-avoiding walks in a diluted lattice at the percolation threshold is determined by a fixed point, different from the pure-lattice one. The full phase diagram of this system is obtained by a real-space renormalization-group treatment and five nontrivial fixed points are identified. A field-theoretical treatment ...

Carrier-induced ferromagnetism has been observed in several (III,Mn)V semiconductors. We review the theoretical picture of these ferromagnetic semiconductors that emerges from a model with kinetic-exchange coupling between localized Mn spins and valence-band carriers. We discuss the applicability of this model, the validity of a mean-field approximation for its interaction term widely used in t...

Abstract: Effective and rapid mixing is essential for various chemical and biological assays. The present work reports a simple and low-cost micromixer based on magnetofluidic actuation. The device takes advantage of magnetoconvective secondary flow, a bulk flow induced by an external magnetic field, for mixing. A paramagnetic stream of diluted ferrofluid and a non-magnetic stream are introduce...

Using Monte Carlo techniques, the two–dimensional site–diluted Ising model is studied. In particular, properties of the specific heat, its critical behaviour and the emergence of a non–singular maximum above the transition temperature at moderate concentration of defects, are discussed.

Diluted Ising antiferromagnets in a homogenous magnetic field have a disordered phase for sufficiently large values of the field and for low temperatures. Here, the system is in a domain state with a broad size-distribution of fractal domains. We study the relaxation dynamics of this domain state after removing the external field for two and three dimensions. Using Monte Carlo simulation techni...

We study zero-bias spin separation in (Cd,Mn)Te/(Cd,Mg)Te diluted magnetic semiconductor structures. The spin current generated by electron gas heating under terahertz radiation is converted into a net electric current by applying an external magnetic field. The experiments show that the spin polarization of the magnetic ion system enhances drastically the conversion process due to giant Zeeman...

We show that the interplay of geometric criticality and quantum fluctuations leads to a novel universality class for the percolation quantum phase transition in diluted magnets. All critical exponents involving dynamical correlations are different from the classical percolation values, but in two dimensions they can nonetheless be determined exactly. We develop a complete scaling theory of this...

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