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Spin logics provide a shortcut toward logic-in-memory architectures. Here, using a T-type magnetic stack with a perpendicular magnetic layer, an in-plane layer, and a spacing layer in between, we can switch both the in-plane and perpendicular layers and independently control their magnetization without an external magnetic field. By initializing magnetization of the in-plane layer, we can further control chirality (clockwise and counterclockwise) of the current-dependence of perpendicular magnetization. Based on these properties and the majority gate theory, we experimentally construct five Boolean logic gates in a single device in the desired field-free condition, which steps forward to practical spin–orbit torque logics.

Metallic LaAlO$_3$/SrTiO$_3$ (LAO/STO) interfaces attract enormous attention, but the relationship between the electron mobility and the sheet electron density, $n_s$, is poorly understood. Here we derive a simple expression for the three-dimensional electron density near the interface, $n_{3D}$, as a function of $n_s$ and find that the mobility for LAO/STO-based interfaces depends on $n_{3D}$ in the same way as it does for bulk doped STO. It is known that undoped bulk STO is strongly compensated with $N \simeq 5 \times 10^{18}~\rm{cm^{-3}}$ background donors and acceptors. In intentionally doped bulk STO with a concentration of electrons $n_{3D} < N$ background impurities determine the electron scattering. Thus, when $n_{3D} < N$ it is natural to see in LAO/STO the same mobility as in the bulk. On the other hand, in the bulk samples with $n_{3D} > N$ the mobility collapses because scattering happens on $n_{3D}$ intentionally introduced donors. For LAO/STO the polar catastrophe which provides electrons is not supposed to provide equal number of random donors and thus the mobility should be larger. The fact that the mobility is still the same implies that for the LAO/STO the polar catastrophe model should be revisited., 4 pages and 1 figure

The two-dimensional electron gas (2DEG) at the non-isostructural interface between spinel gamma-Al2O3 and perovskite SrTiO3 is featured by a record electron mobility among complex oxide interfaces in addition to a high carrier density up to the order of 1E15 cm-2. Herein, we report on the patterning of 2DEG at the gamma-Al2O3/SrTiO3 interface grown at 650 {\deg}C by pulsed laser deposition using a hard mask of LaMnO3. The patterned 2DEG exhibits a critical thickness of 2 unit cells of gamma-Al2O3 for the occurrence of interface conductivity, similar to the unpatterned sample. However, its maximum carrier density is found to be approximately 3E13 cm-2, much lower than that of the unpatterned sample (1E15 cm-2). Remarkably, a high electron mobility of approximately 3,600 cm2V-1s-1 was obtained at low temperatures for the patterned 2DEG at a carrier density of 7E12 cm-2, which exhibits clear Shubnikov-de Hass quantum oscillations. The patterned high-mobility 2DEG at the gamma-Al2O3/SrTiO3 interface paves the way for the design and application of spinel/perovskite interfaces for high-mobility all-oxide electronic devices., Comment: 4 figures

We report an enhanced performance of multi-scale textured black silicon solar cell with power conversion efficiency of 15.5% by using anisotropic tetramethylammonium hydroxide etching to control the recombination. The multi-scale texture can effectively reduce the surface reflectance in a wide wavelength range, and both the surface and Auger recombination can be effectively suppressed by etching the samples after the n++ emitter formed. Our result shows that the reformed solar cell has higher conversion efficiency than that of conventional pyramid textured cell (15.3%). This work presents an effective method for improving the performance of nanostructured silicon solar cells.

Angular dependent magnetoresistance (AMR) phenomena in Pr0.7Ca0.3MnO3 film have been investigated. A transition between cos2θ dependent AMR in an insulating state at low fields and sin2θ dependent AMR in a metal state at high fields is observed at intermediate fields, depending on the temperature and/or strength of an applied magnetic field. Although the AMR sign evolution process from cos2θ dependence to sin2θ dependence at low temperature is different from that at high temperature due to existence of ferromagnetic insulator besides charge ordering antiferromagnetic insulator, we believe that such AMR sign evolutions are closely related with magnetic-field-induced ferromagnetic metal percolation behavior.

The angular dependent magnetoresistance (AMR) of Nd0.45Sr0.55MnO3 thin film epitaxially grown on SrTiO3 (001) is examined at different temperatures and magnetic fields. Twofold and fourfold symmetric AMR and a transition between them are observed under two different measurement modes and are found to be dependent on temperature and/or strength of a magnetic field. In comparison with AMR occurring in other systems, we believe that the twofold/fourfold symmetric AMR observed here corresponds to different spin-canted states induced by the magnetic field at certain temperatures below the Neel temperature.

The lattice parameter of bismuth nanowires has been measured using the in situ high-temperature x-ray diffraction method. Single-crystalline Bi nanowire arrays with the diameters from 10nmto250nm have been fabricated within the porous anodic alumina membranes by a pulsed electrodeposition technique. Different temperature dependencies of lattice parameter and thermal expansion coefficient were found for Bi nanowires with different diameters, and there is a transition from positive thermal expansion coefficient at low temperature to negative one at high temperature, and the transition temperature shifts to high temperature with the increase in the diameter of Bi nanowires.