A significant decrease is observed in the dielectric dispersion, conductivity, coercive and internal fields of KTiOPO4 crystals grown with relatively high potassium concentration in the flux. A periodic domain structure with a period of 24.7 mm was fabricated on a 10 mm long crystal by electric field poling. Whereas standard flux-grown KTiOPO4 crystals can be periodically poled only at low temp...

We report direct measurements of the charging diagram of a nanoscale series double-dot system at low temperatures. Our device consists of two metal dots in series, with each dot capacitively coupled to another single dot serving as an electrometer. This configuration allows us to externally detect all possible charge transitions within a double-dot system. In particular, we show that transfer o...

1. Introduction The wetland is mostly distributed in the moist low temperature area at high latitudes. The wetland has the peat bog, which forms the accumulation of undecomposed plants. The important thing to notice is that the peat bog is similar to the aerial part of biomass in accumulating carbon. Since the amount of carbon cannot be ignored in the wetland, there is an urgent need to monitor...

The spin-exchange collision cross-section for hydrogen atoms has been measured for the first time in the low temperature range 40–100 K by using the polarized hydrogen gas target of the HERMES experiment at DESY (Hamburg, Germany). The results agree with a previous measurement in the overlapping temperature region 80–100 K, while seem to hint an increasing behaviour with temperature in the regi...

The efficiency droop in GaInN/GaN multiple-quantum well MQW light-emitting diodes is investigated. Measurements show that the efficiency droop, occurring under high injection conditions, is unrelated to junction temperature. Furthermore, the photoluminescence output as a function of excitation power shows no droop, indicating that the droop is not related to MQW efficiency but rather to the rec...

In two loop effective Lagrangian, the low temperature expansion of the QED3+1 with a constant magnetic field and a finite chemical potential is performed. We then calculate the total fermion density, some components of polarization operator and de Hass -van Alphen oscillations. We find that there is a significant contribution from two-loop expansion to magnetization and fermion density for high...

We consider the exciton states in quasi-one-dimensional organic crystals with strong orbital overlap between neighboring molecules. In such crystals, the energy di€erence between the lowest Frenkel exciton and the nearestneighbor charge-transfer excitons becomes small and their strong mixing determines the nature of the lowest energy states. We discuss these e€ects for crystalline N ,N 0-dimeth...

Several polycrystalline samples of the half-Heusler alloy NiMnSb were grown by arc melting of stoichiometric and nonstoichiometric amounts of high-purity constituent elements. The structure and the phase-purity of the prepared samples were examined systematically by powder x-ray diffraction. The transport properties of the best sample, with saturation magnetization M s(5 K) 54 mB/formula unit, ...

We report on magnetoresistance oscillations in superconducting NbNx nanowires synthesized through ammonia gas annealing of NbSe3 precursor nanostructures. Though the transverse dimensions of the nanowires are much larger than the superconducting coherence length, the voltage-current characteristics of these nanowires at low temperatures are reminiscent of onedimensional superconductors where qu...