[Luminescent control of the functional condition of Vallisneria spiralis L. treated by microwave irradiation].

The influence of microwave emission on the Vallisneria spiralis L. photoluminescence (PL) is studied. It is found that the irradiation leads to degradation of all the luminescence spectrum bands. It is shown that the influence on the chlorophyll PL at 715-735 and 800 nm is not limited by accompanied temperature effect. The degradation of PL has a temperature threshold at the thermal treatment. The 725 nm luminescence band of chlorophyll is shifted to short waves at both the irradiation and thermal treatment. The shift dependence from the irradiation dose and temperature is non-monotonous.

Band offsets and photocurrent spectroscopy of Si/Ge heterostructures with quantum dots.

Raman and lateral photoconductivity spectra of self-assembled SiGe nanoislands were studied with a height of ∼2 nm and a base of ∼20 nm formed at a temperature of 500 °C. It was estimated that the value of elastic deformation (ε(xx)) was -0.022 (ε(zz) = 0.017), while the germanium content in the islands (x) was 0.66. The obtained values of x and ε were used to calculate band offsets at the interfaces and the energy of interband transitions of structures under study. It was shown that the minimal energy of photocurrent observation is 0.52 eV, which is below the bandgap of the QDs under study. The first photocurrent component which began to contribute at 0.52 eV and had a peak at 0.68 eV is explained by optical transitions of electrons from the QD HH localized states of the valence band to the conduction band Δ(2) valley of the surrounding silicon matrix in which tensile strains are present. The second component with limiting energy of 0.73 eV can be caused by interband electron transitions from the HH valence band of the QDs to the Δ(4) valley of the QD conduction band.