Carbon nanotubes have interesting electromechanical properties that may enable a new class of nanoscale mechanical sensors. We fabricated two-terminal nanotube devices on silicon nitride membranes, measured their electronic transport versus strain, and estimated their band gaps and the strain-induced changes in them. We found band-gap increases and decreases among both semiconducting and small-gap semiconducting (SGS) tubes. The SGS band gaps exceeded the predicted curvature-induced gaps for their diameter. Some of the band-gap changes for both types of tubes exceeded the predicted maxima. These anomalies are likely caused by interaction with the rough silicon nitride surface.

Laser-cooled neutral atoms from a low-velocity atomic source are guided via a magnetic field generated between two parallel wires on a glass substrate. The atoms bend around three curves, each with a 15-cm radius of curvature, while traveling along a 10-cm-long track. A maximum flux of 2 · 10 6 atoms/sec is achieved with a current density of 3 · 10 4 A/cm 2 in the 100 × 100-µm-cross-section wires. The kinetic energy of the guided atoms in one transverse dimension is measured to be 42 µK. PACS numbers: 03.75.B, 32.80.P Just as optical waveguides play a central role in many aspects of modern optics, from communications to integrated optics, atom waveguides are likely to be an enabling technology for future atom-optics-based science. In particular, well-characterized atom waveguides may make possible inertial and rotation measurements of exquisite sensitivity via large-enclosed-area atom interferometers [1]. One of the first guides for atoms was based on optical forces, where hollow glass fibers guide light, and the light in turn guides atoms [2,3].Atom guiding using magnetic forces from current-carrying wires has been demonstrated more recently [4,5]. From the point-of-view of using atom-guides to pursue precision metrology goals [6] much benefit can be derived from patterning the waveguides on a rigid substrate. First, beamsplitters can be precisely and reproducibly fabricated.Second, the enclosed area of an interferometer can be precisely controlled. Third, the use of well-established lithographic techniques means that progress on individual optical elements (a beamsplitter, or a monochromator, for instance) can be rapidly extended to multi-component experiments. Mirrors based on micro-patterned wires have already been introduced [7]. We report magnetic guiding by a pair of parallel wires produced on a glass substrate by photolithography and subsequent electro-plating. Intricate two-dimensional guiding structures are easily produced by this manufacturing technique; in the present case, it allows us to demonstrate guiding around curves in a 10 cm long

We present a micromachined scanning probe cantilever, in which a specific higher-order flexural mode is designed to be resonant at an exact integer multiple of the fundamental resonance frequency. We have fabricated such cantilevers by reducing the stiffness of the third order flexural mode relative to the fundamental mode, and we have demonstrated that these cantilevers enable sensing of non-linear mechanical interactions between the atomically sharp tip at the free end of the cantilever and a surface with unknown mechanical properties in tapping-mode atomic force microscopy. Images of surfaces with large topographical variations show that for such samples harmonic imaging has better resolution than standard tapping-mode imaging. © 2003 Elsevier B.V. All rights reserved

We have developed an atomic force microscope that uses interferometry for parallel readout of a cantilever array. Each cantilever contains a phase sensitive diffraction grating consisting of a reference and movable set of interdigitated fingers. As a force is applied to the tip, the movable set is displaced and the intensity of the diffracted orders is altered. The order intensity from each cantilever is measured with a custom array of silicon photodiodes with integrated complementary metal-oxide-semiconductor amplifiers. We present images from five cantilevers acquired in the constant height mode that reveal surface features 2 nm in height. The interdigital method for cantilever array readout is scalable, provides angstrom resolution, and is potentially simpler to implement than other methods. © 2001 American Institute of Physics

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