A biotemplated nanomaterial can include a crystalline perovskite.

Systems and methods are disclosed for rapid growth of Group III metal nitrides using plasma assisted molecular beam epitaxy. The disclosure includes higher pressure and flow rates of nitrogen in the plasma, and the application of mixtures of nitrogen and an inert gas. Growth rates exceeding 8 ?m/hour can be achieved.

Systems and methods are disclosed for rapid growth of Group III metal nitrides using plasma assisted molecular beam epitaxy. The disclosure includes higher pressure and flow rates of nitrogen in the plasma, and the application of mixtures of nitrogen and an inert gas. Growth rates exceeding 8 ?m/hour can be achieved.

[Object]

It is an object of the present invention to provide a lithium tantalate single crystal substrate which undergoes only small warpage, is free from cracks and scratches, has better temperature non-dependence characteristics and a larger electromechanical coupling coefficient than a conventional Y-cut LiTaO.sub.3 substrate.

[Means to Solve the Problems]

The lithium tantalate single crystal substrate of the present invention is a rotated Y-cut LiTaO.sub.3 single crystal substrate having a crystal orientation of 36 Y-49 Y cut characterized in that: the substrate is diffused with Li from its surface into its depth such that it has a Li concentration profile showing a difference in the Li concentration between the substrate surface and the depth of the substrate; and the substrate is treated with single polarization treatment so that the Li concentration is substantially uniform from the substrate surface to a depth which is equivalent to 5-15 times the wavelength of either a surface acoustic wave or a leaky surface acoustic wave propagating in the LiTaO.sub.3 substrate surface.

The lithium tantalate single crystal substrate is a rotated Y-cut LiTaO.sub.3 single crystal substrate having a crystal orientation of 36 Y-49 Y cut characterized in that: the substrate is diffused with Li from its surface into its depth such that it has a Li concentration profile showing a difference in the Li concentration between the substrate surface and the depth of the substrate; and the substrate is treated with single polarization treatment so that the Li concentration is substantially uniform from the substrate surface to a depth which is equivalent to 5-15 times the wavelength of either a surface acoustic wave or a leaky surface acoustic wave propagating in the LiTaO.sub.3 substrate surface.

A device configured to convert or amplify a particle, the conversion or amplification being reliant on the impact of a particle on a surface of the device causing emission of one or more secondary electrons from the same surface. The device includes a carbon-based layer capable of secondary electron emission upon impact of a particle. The surface may be used to convert, for example, an ion into an electron signal, or an electron signal into an amplified electron signal, such as in conversion or amplification dynodes.

A device configured to convert or amplify a particle, the conversion or amplification being reliant on the impact of a particle on a surface of the device causing emission of one or more secondary electrons from the same surface. The device includes a carbon-based layer capable of secondary electron emission upon impact of a particle. The surface may be used to convert, for example, an ion into an electron signal, or an electron signal into an amplified electron signal, such as in conversion or amplification dynodes.

Methods and systems are provided for a homogenous, single crystal, electrically conductive, and narrow bandgap PbSe nanostructure is synthesized using a chemical bath deposition on, for example, quartz substrates, and includes a tunable iodine doping process to select the size and/or shape of the nanostructures. The single crystalline PbSe nanostructure can be exposed following an isolation process (e.g., etching process), and the concentration and/or distribution of iodine across multiple PbSe nanostructures (e.g., on a quartz substrate) can be adjusted during post processing steps, including heat treatments.

Methods and systems are provided for a homogenous, single crystal, electrically conductive, and narrow bandgap PbSe nanostructure is synthesized using a chemical bath deposition on, for example, quartz substrates, and includes a tunable iodine doping process to select the size and/or shape of the nanostructures. The single crystalline PbSe nanostructure can be exposed following an isolation process (e.g., etching process), and the concentration and/or distribution of iodine across multiple PbSe nanostructures (e.g., on a quartz substrate) can be adjusted during post processing steps, including heat treatments.

A method of growing large GaAs or GaP IR window slabs by HVPE, and in embodiments by LP-HVPE, includes obtaining a plurality of thin, single crystal, epitaxial-quality GaAs or GaP wafers, cleaving the wafers into tiles having ultra-flat, atomically smooth, substantially perpendicular edges, and then butting the tiles together to form an HVPE substrate larger than 4 inches for GaP, and larger than 8 inches or even 12 inches for GaAs. Subsequent HVPE growth causes the individual tiles to fuse by optical bonding into a large tiled single crystal wafer, while any defects nucleated at the tile boundaries are healed, causing the tiles to merge with themselves and with the slab with no physical boundaries, and no degradation in optical quality. A dopant such as Si can be added to the epitaxial gases during the final HVPE growth stage to produce EMI shielded GaAs windows.