Related papers: Noise studies of magnetization dynamics in dilute …
A recent preprint [arxiv:1807.08572] has reported the observation of room temperature supercondutivity in a nanostructured solid composed of gold and silver nanocrystals. Given the extraordinary and exciting nature of this claim, it is…
The effect of improved dielectric properties in the presence of an applied magnetic field is discussed in Pr doped polycrystalline Gd$_{0.55}$Pr$_{0.45}$MnO$_3$ complemented by the structural properties down to 50 K and magnetic properties.…
We present experimental results on thermoelectric power ({\em S}) and electrical resistivity ($\rho $) of pseudobinary alloys Ho(Al$_x$Co$_{1-x}$)$_2$ ($0 \leq x \leq 0.1 $), in the temperature range 4.2 K to 300 K. The work focuses on the…
Thermodynamical fluctuations of temperature in mirrors of gravitational wave antennae are transformed through thermal expansion coefficient into additional noise. This source of noise, which may also be interpreted as fluctuations due to…
The rapidly developing field of ferromagnetism in diluted magnetic semiconductors, where a semiconductor host is magnetically doped by transition metal impurities to produce a ferromagnetic semiconductor (e.g. Ga_{1-x}Mn_xAs with x ~ 1-10…
The influence of configurational disorder on the magnetic properties of diluted Heisenberg spin systems is studied with regard to the ferromagnetic stability of diluted magnetic semiconductors. The equation of motion of the magnon Green's…
We studied electronic relaxation in long diffusive superconductor / normal metal / superconductor (S/N/S) junctions by means of current noise and transport measurements down to very low temperature (100mK). Samples with normal metal lengths…
Electron spins in silicon have long coherence times and are a promising qubit platform. However, electric field noise in semiconductors poses a challenge for most single- and multi-qubit operations in quantum-dot spin qubits. Here, we…
Slow magnetic relaxation and two level fluctuations measurements under high current injection is performed in single-contacted ferromagnetic nanostructures. The magnetic configurations of the samples are described by two metastable states…
A new diluted ferromagnetic semiconductor (Sr,Na)(Zn,Mn)2As2 is reported, in which charge and spin doping are decoupled via Sr/Na and Zn/Mn substitutions, respectively, being distinguished from classic (Ga,Mn)As where charge & spin doping…
The carrier spin and impurity spin densities in diluted magnetic semiconductors are considered using a semiclassical approach. Equations of motions for the spin densities and the carrier spin current density in the paramagnetic phase are…
By combining experimental measurements of the quasiparticle and dynamical magnetic properties of optimally electron-doped Pr$_{0.88}$LaCe$_{0.12}$CuO$_4$ with theoretical calculations we demonstrate that the conventional fermiology approach…
Fluctuations of electric fields can change the position of a gate-defined quantum dot in a semiconductor heterostructure. In the presence of magnetic field gradient, these stochastic shifts of electron's wavefunction lead to fluctuations of…
We fabricated an etched hole quantum dot in a Si-doped (311)A AlGaAs/GaAs heterostructure to study disorder effects via magnetoconductance fluctuations (MCF) at millikelvin temperatures. Recent experiments in electron quantum dots have…
We study energetic, magnetic, and electronic properties of diluted substitutional Mn-pairs on the reconstructed $(001)$ GaAs surfaces. The studies are based on first-principles calculations in the framework of the density functional theory.…
A general scheme is developed to analyze the effect of non-uniform thermal magnetization fluctuations in a thin film. The normal mode formalism is utilized to calculate random magnetization fluctuations. The magnetization noise is…
We suggest to use `fluctuation spectroscopy' as a method to detect granularity in a disordered metal close to a superconducting transition. We show that with lowering temperature $T$ the resistance $R(T)$ of a system of relatively large…
We calculate fluctuation corrections to the longitudinal conductivity of disordered superconductors subject to an external magnetic field. We derive analytic expressions that are valid in the entire metallic part of the temperature-magnetic…
Shot-noise measures the correlations of fluctuations of current for a voltage applied much larger than the temperature and reveals aspects of correlations in fermions beyond those revealed in the conductivity. Recent measurements of…
We numerically investigate sound damping in a model of granular materials in two dimensions. We simulate evolution of standing waves in disordered frictionless disks and analyze their damped oscillations by velocity autocorrelation…