In this paper, we present differential cross sections and complete sets of polarization transfer coefficients, D i j , obtained in the 13 C(p ជ ,n ជ) 13 N reaction studied at zero degree and at 197 MeV incident proton energy. The complete set of polarization observables is used to obtain the Fermi and Gamow-Teller ͑GT͒ cross section contributions in the ground state transition, which are then used to deduce GT transition strengths. The sum of the GT strength up to 20 MeV of excitation is compared with shell model calculations. In the region between 20 to 46 MeV of excitation, the differential cross section has been separated in spin and nonspin components.

Two-dimensional electron systems with fascinating properties exist in multilayers of standard semiconductors, on helium surfaces, and in oxides. Compared to the two-dimensional (2D) electron gases of semiconductors, the 2D electron systems in oxides are typically more strongly correlated and more sensitive to the microscopic structure of the hosting lattice. This sensitivity suggests that the oxide 2D systems are highly tunable by hydrostatic pressure. Here we explore the effects of hydrostatic pressure on the well-characterized 2D electron system formed at LaAlO3-SrTiO3 interfaces 1 and measure a pronounced, unexpected response. Pressure of ∼2 GPa reversibly doubles the 2D carrier density ns at 4 K. Along with the increase of ns, the conductivity and mobility are reduced under pressure. First-principles pressure simulations reveal the same behavior of the carrier density and suggest a possible mechanism of the mobility reduction, based on the dielectric properties of both materials and their variation under external pressure.

We have manufactured oxide field-effect transistors using the electron system at the LaAlO3-SrTiO3 interface as a drain-source channel and measured the devices under a hydrostatic pressure of up to 1.8 GPa. These studies of oxide transistors in the high-pressure regime demonstrate remarkable stability of the devices against gate leakage and resilience to mechanical strain. They show that oxide transistors can be operated in a wide range of pressures and temperatures and open the road for future studies of oxide materials and their possible applications in electronics.

grasp of the underlying science. This situation has changed greatly with our growing understanding of nanoscience, particularly with regard to the role of size effects. Indeed, owing to quantum confinement and surface effects, material properties begin to differ from the bulk at a length scale below ≈100 nm. [2] These effects can impact the electronic, thermal, chemical, and optical properties of a material at the nanoscale. The study of nanocrystals is the driving force behind innovations in electronic, [1,3] optoelectronic, [4,5] and nanophoto nic [6] devices. In addition, nanocrystals are used for catalysis [7,8] and medical applications. [9,10] Nanostructures and nanocrystals are usually fabricated by well-known top-down or bottom-up approaches. [2,[11][12][13] In this contribution, we focus on a distinct third method to create nanocrystalline structures, which combines aspects of those two approaches. Our method utilizes the self-assembly of nanocrystalline structures through thinfilm agglomeration. [14,15] Applying recent developments in epitaxial growth and liftoff of thin films to form membranes, it presents a general framework for achieving self-assembly. The agglomeration achieved by an architectured dewetting process will be described in the following discussion.In the process of annealing a thin film deposited on a substrate, a variety of mass transport phenomena such as surface diffusion, intermixing, evaporation, and condensation may take place (Figure 1). Mass transport occurring on the edge of a film can retract the film to minimize the total surface energy. This process reduces the coverage of the substrate by the film and eventually forms islands of material resting on the substrate. [14,[16][17][18] This inherent ability of thin films to dewet on surfaces and to agglomerate into islands is leveraged to form crystalline nanoparticles to fabricate catalysis [19][20][21][22] as well as electronic [23,24] and nanophotonic devices. [25][26][27][28] This process provides a way to achieve high-throughput nanofabrication [25] of highly oriented and faceted nanostructures that are not obtainable with traditional lithography and etching methods. [29][30][31][32][33][34][35] Dewetting has been studied extensively, both theoretically and experimentally, in single-crystal configurations of elements [31,32,[36][37][38] such as palladium, [39] nickel, [38,40] and silicon, [18,30] which has yielded a detailed understanding of The exploration of crystalline nanostructures enhances the understanding of quantum phenomena occurring in spatially confined quantum matter and may lead to functional materials with unforeseen applications. A novel route to fabricating nanocrystalline oxide structures of exceptional quality is presented. This is achieved by utilizing a self-assembly process of ultrathin membranes composed of the desired oxide. The thermally induced self-assembly of nanocrystalline structures is driven by dewetting the oxide membranes once they are lifted off and transferred onto sapphire surfaces. In thr...

We present a method to perform electrical measurements of epitaxial films and heterostructures a few nanometers thick under high hydrostatic pressures in a diamond anvil cell (DAC). Hydrostatic pressure offers the possibility to tune the rich landscape of properties shown by epitaxial heterostructures, systems in which the combination of different materials, performed with atomic precision, can give rise to properties not present in their individual constituents. Measuring electrical conductivity under hydrostatic pressure in these systems requires a robust method that can address all the challenges: the preparation of the sample with side length and thickness that fits in the DAC setup, a contacting method compatible with liquid media, a gasket insulation that resists high forces, as well as an accurate procedure to place the sample in the pressure chamber. We prove the robustness of the method described by measuring the resistance of a two dimensional electron system buried at the interface between two insulating oxides under hydrostatic conditions up to ∼5 GPa. The setup remains intact until ∼10 GPa, where large pressure gradients affect the two dimensional conductivity.