Authors interpreted their results as evidence for Ps-like Bloch states. Later, Bloch states of Ps were observed in alkali halides and Ps effective STI571 supplier mass was measured in NaBr and RbCl crystals [31]. In particular, the temperature dependence of the transition from a self-trapped Ps to the Bloch state was

investigated. It is natural to assume that by creating a jump of the potentials on the boundaries of the media with the selection of specific materials with different widths of the bandgaps, it will be possible to localize the Bloch state of the Ps in a variety of nanostructures. There are many works devoted to the study of the Ps states in various solids or on their surfaces. The work functions of the positron and Ps for metals and semiconductors are calculated in [32]. It is remarkable that the Ps and metal surface interaction is mainly conditioned by the attractive van der Waals polarization interaction at large distances [33]. The interaction becomes repulsively close to the surface due to the Ps and surface electrons’ wave functions overlapping. The calculated energy of the formed bound state of Ps on the metal surface is in perfect agreement with the experimentally measured value [34]. Calculations of positron energy levels and work functions of the positron and Ps in the case of narrow-gap semiconductors are given in the paper [35]. It should be noted CDK activation that in the narrow-gap semiconductors, in addition to reduction

of the bandgap, the dispersion law of CCs is complicated as well. However, there are quite a number of papers in which more complicated dependence of the CC effective mass on the energy is considered [11–14, 36–39] in the framework of Kane’s theory. For example, for the narrow-gap QDs of InSb, the dispersion law of CCs is nonparabolic, and it is well described by Kane’s two-band mirror model [14, 40]. Within the framework of the two-band approximation, the electron (light hole) Anidulafungin (LY303366) dispersion law formally coincides with the relativistic law. It is known that in the case of Kane’s dispersion

law, the binding energy of the impurity center turns out more than that in the case of the parabolic law [40, 41]. It is also known that reduction of the system dimensionality leads to the increase in Coulomb Selleck R406 quantization. Hence, in the two-dimensional (2D) case, the ground-state binding energy of the impurity increases four times compared to that of the three-dimensional (3D) case [42]. As the foregoing theoretical analysis of Ps shows, the investigation of quantum states in the SQ semiconductor systems with Kane’s dispersion law is a prospective problem of modern nanoscience. In the present paper, the quantum states of the electron-positron pair in the spherical and circular QDs consisting of InSb and GaAs with impermeable walls are considered. The quantized states of both Ps and individually quantized electron and positron are discussed in the two SQ regimes – weak and strong, respectively.