Flux-pinning mechanism of MgB2 doped with 10 wt % silicone-oil sintered at low and high temperatures has been investigated by magnetic measurements. The field dependence of the critical current density, jc(B), was analysed within the collective pinning model. A crossover field, Bsb, from the single vortex to the small vortex bundle-pinning regime was observed. For both types of sintered samples...

We prove that for q ≥ 1, there exists r(q) < 1 such that for p > r(q), the number of points in large boxes which belongs to the infinite cluster has a normal central limit behaviour under the random cluster measure φp,q on Z, d ≥ 2. Particularly, we can take r(q) = p∗g for d = 2, which is commonly conjectured to be equal to pc. These results are used to prove a qdimensional central limit theore...

Single molecule spectroscopy reveals fascinating fluctuation behaviors, not observed in standard spectroscopies, for example spectral jumps, blinking, photon bunching and anti bunching. We investigate the theory of time dependent fluctuations of single molecule fluorescence. In particular the relation between spectral diffusion, found in many single molecule experiments, and photon counting sta...

The width of the giant dipole resonance (GDR) built on excited states was determined from a measurement of γ -decays in coincidence with 17O particles scattered inelastically from 120Sn. The bombarding energy was 80 MeV/u. A width of 4 ± 1 MeV, consistent with the width of the GDR built on the ground state, was found at a temperature T = 1 MeV. This result is in disagreement with adiabatic ther...

Detailed measurements of the voltage, temperature, and frequency dependence of the nonequilibrium current fluctuations for a diffusive mesoscopic conductor are reported. The data confirm predictions that a mesoscopic conductor shorter than the electron-electron inelastic length will display shot noise. Furthermore, the low temperatures (100 mK) and high frequencies (1–20 GHz) used for the measu...

The results of high precision measurements of the dielectric susceptibility ε(T ) of solid oxygen in the low temperature α and β phases that have highly frustrated orientational interactions, are compared with the results of earlier studies of the thermal behavior of ε(T ) in solid N2-Ar mixtures. In the latter case the combination of disorder and frustration results in orientational glass stat...

We investigate the particle-number fluctuations of condensate due to collective excitations for trapped two-dimensional (2D) and quasi-2D Bose gases at low temperature. We show that the fluctuations of the condensate are proportional to the square of the total particle number of the system. For a quasi-2D Bose gas the fluctuations are also proportional to the square root of the trapping frequen...

A previous theory for studying the distribution of non-uniform fields in multiple-quantum-well photodetectors under an ac voltage is generalized by including non-adiabatic space-charge-field effects. Numerical calculations indicate that field-domain effects are only important at high temperatures or high voltages when both injection and sequentialtunneling currents are significant. On the other...

The temperature and magnetic field dependence of llfnoise has been measured in epitaxial YBa2Cu30, films. In a magnetic field, two noise pealcs were observed as temperature decreases; one at higher temperature was found to match the thermal fluctuation of the sample resistance and the other near the foot of the transition was found to be magnetic-field dependent. The location of the latter was ...

BACKGROUND Poor control of body temperature is associated with mortality and major morbidity in preterm infants. We aimed to quantify its dynamics and complexity to evaluate whether indices from fluctuation analyses of temperature time series obtained within the first five days of life are associated with gestational age (GA) and body size at birth, and presence and severity of typical comorbid...