Abstract: This invention generally relates to nanotechnology and nanoelectronics as well as associated methods and devices. In particular, the invention relates to nanoscale optical components such as electroluminescence devices (e.g., LEDs), amplified stimulated emission devices (e.g., lasers), waveguides, and optical cavities (e.g., resonators). Articles and devices of a size greater than the nanoscale are also included. Such devices can be formed from nanoscale wires such as nanowires or nanotubes. In some cases, the nanoscale wire is a single crystal. In one embodiment, the nanoscale laser is constructed as a Fabry-Perot cavity, and is driven by electrical injection. Any electrical injection source may be used. For example, electrical injection may be accomplished through a crossed wire configuration, an electrode or distributed electrode configuration, or a core/shell configuration. The output wavelength can be controlled, for example, by varying the types of materials used to fabricate the device.

Abstract: Methods of positioning and orienting nanostructures, and particularly nanowires, on surfaces for subsequent use or integration. The methods utilize mask based processes alone or in combination with flow based alignment of the nanostructures to provide oriented and positioned nanostructures on surfaces. Also provided are populations of positioned and/or oriented nanostructures, devices that include populations of positioned and/or oriented nanostructures, systems for positioning and/or orienting nanostructures, and related devices, systems and methods.

Abstract: The present invention relates generally to sub-microelectronic circuitry, and more particularly to nanometer-scale articles, including nanoscale wires which can be selectively doped at various locations and at various levels. In some cases, the articles may be single crystals. The nanoscale wires can be doped, for example, differentially along their length, or radially, and either in terms of identity of dopant, concentration of dopant, or both. This may be used to provide both n-type and p-type conductivity in a single item, or in different items in close proximity to each other, such as in a crossbar array. The fabrication and growth of such articles is described, and the arrangement of such articles to fabricate electronic, optoelectronic, or spintronic devices and components.

Abstract: A bulk-doped semiconductor that is at least one of the following: a single crystal, an elongated and bulk-doped semiconductor that, at any point along its longitudinal axis, has a largest cross-sectional dimension less than 500 nanometers, and a free-standing and bulk-doped semiconductor with at least one portion having a smallest width of less than 500 nanometers. Such a semiconductor may comprise an interior core comprising a first semiconductor; and an exterior shell comprising a different material than the first semiconductor. Such a semiconductor may be elongated and my have, at any point along a longitudinal section of such a semiconductor, a ratio of the length of the section to a longest width is greater than 4:1, or greater than 10:1, or greater than 100:1, or even greater than 1000:1.