InAs nanowire with 〈110〉 orientation is proposed for use as an electron spin transport channel for application to spintronics devices, particularly the Datta–Das spin transistor. Stable zinc blende crystal NWs were grown using a molecular beam epitaxy system. Subsequently, global back-gate NW field effect transistors were fabricated, and the superiority of the electrical transport properties within our resultant 〈110〉 NWs was demonstrated by comparing the field-effect mobility with a 〈111〉 NW control sample. Additionally, single NW Hall-bar devices were fabricated, which allowed us to obtain the transport properties accurately, and Hall effect measurements were successfully taken at different temperatures.

Lead free piezoelectric single crystals of sodium potassium niobate (K 0.5 Na 0.5 )NbO 3 (KNN) were grown by high-temperature solution method using two different fluxes; one with a mixture of NaF and KF and other with addition of B 2 O 3 along with the mixture. In the present study, the growth of KNN crystals without B 2 O 3 flux and the same with B 2 O 3 flux were compared. It was found that additions of small amounts of B 2 O 3 lowered the melting temperature of the solid solution and enabled better dielectric properties. Phase analysis showed that all samples were crystallized in pure orthorhombic perovskite phase. AFM morphological studies showed that the addition of B 2 O 3 flux increased the roughness of the grown crystal. Further, addition of B 2 O 3 flux slightly decreased the orthorhombic to tetragonal phase transition temperature T (O-T) and the Curie temperature T C . The ferroelectric behaviour of KNN single crystal has been investigated at room temperature. The crystal grown using B 2 O 3 flux exhibited a remanent polarization (P r ) ∼ 32 μC/cm 2 and coercive field (Ec) of ∼11.8 kV/cm whereas the crystal grown without the use of B 2 O 3 flux had a remanent polarization (P r ) ∼ 36 μC/cm 2 and coercive field (Ec) of ∼14.6 kV/cm.

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Nanoporous gallium nitride (GaN) has many potential applications in light-emitting diodes (LEDs), photovoltaics, templates and chemical sensors. This article reports the porosification of GaN through UV enhanced metal-assisted electroless photochemical wet etching technique using three different acid-based etchants and platinum served as catalyst for porosification. The etching process was conducted at room temperature for a duration of 90[Formula: see text]min. The morphological, structural, spectral and optical features of the developed porous GaN were studied with appropriate characterization techniques and the obtained results were presented. Field emission scanning electron micrographs exhibited the porosity nature along with excellent porous network of the etched samples. Structural studies confirmed the mono crystalline quality of the porous nanostructures. Raman spectral analyzes inferred the presenting phonon modes such as E2 (TO) and A1 (LO) in fabricated nanoporous structures. The resulted porous nanostructures hold the substantially enhanced photoluminescence intensity compared with the pristine GaN epitaxial film that is interesting and desirable for several advances in the applications of Nano-optoelectronic devices.