Особенности роста наноструктур для терагерцовых квантово-каскадных лазеров и их физические свойства

The data on the synthesis and characterization of structures for a quantum cascade terahertz laser in an AlGaAs/GaAs material system on GaAs substrates using the molecular beam epitaxy method are presented. The features necessary for the implementation of such structures are considered. It was shown that for this geometry almost single-mode lasing is observed at a frequency of ∼ 3 THz up to a temperature of ∼ 60 K.

Раскрытие энергетической щели в области точки Дирака при осаждении кобальта на поверхность (0001) топологического изолятора BiSbTeSe-=SUB=-2-=/SUB=-

It was shown for the first time that Co subnanometer coaverage, being deposited by molecular beam epitaxy method onto the (0001) surface of the BiSbTeSe2 topological insulator at 330 °C, opens an energy band gap in the spectrum of topological surface states in the region of the Dirac point, with a shift in the position of the Dirac point caused by preliminary deposition of the adsorbate at room temperature. The gap band width is 21 +/- 6 meV. Temperature-dependent measurements in the 15-150 K range did not show any width changes.

Fabrication of Dielectric/Conductive Hybrid Artificial Superlattices Using Molecular Beam Epitaxy Method

Artificial super-lattices of [(BaTiO3)/(SrTiO3)10]4 (BTO10/STO10) were fabricated on STO(001) substrate by the molecular beam epitaxy method (MBE), and the molecular layers of SrRuO3(SRO) was introduced into these superlattices as conductive layers. The superlattices introduced two conductive layers showed the enormous dielectric permittivity. On the other hand, the permittivity of the superlattice introduced one conductive layer was almost same as that of BTO10/STO10. In the case of introducing two conductive layers, the moving electrons between two layers induced the interfacial polarization. Especially, the superlattice with two SRO conductive layers, the distance between these layers in a superlattice is 18 molecular layers, showed the highest relaxation frequency 132 kHz and biggest capacitance.