Jonathan E. Hoffman

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Two experiments investigated a model for global procedence, which states that global aspects of a form are invariably recognized prior to local levels. Experiment 1 showed that speed of recognition was approximately the same for global and local levels of a form. Experiment 2 independently manipulated the "quality" of information at global and local levels(More)
Optical nanofibers (ONFs) provide a rich platform for exploring atomic and optical phenomena even when they support only a single spatial mode. Nanofibers supporting higher-order modes (HOMs) provide additional degrees of freedom to enable complex evanescent field profiles for interaction with the surrounding medium, but local control of these profiles(More)
We report controlled local manipulation of single vortices by low temperature magnetic force microscopy in a thin film of superconducting Nb. We are able to position the vortices in arbitrary configurations and to measure the distribution of local depinning forces. This technique opens up possibilities for the characterization and use of vortices in(More)
Measurement instruments and fabrication tools with spatial resolution on the atomic scale require facilities that mitigate the impact of vibration sources in the environment. One approach to protection from vibration in a building's foundation is to place the instrument on a massive inertia block, supported on pneumatic isolators. This opens the questions(More)
The development of optical nanofibers (ONF) and the study and control of their optical properties when coupling atoms to their electromagnetic modes has opened new possibilities for their use in quantum optics and quantum information science. These ONFs offer tight optical mode confinement (less than the wavelength of light) and diffraction-free(More)
Quantized magnetic flux tubes, called vortices, allow superconductivity to survive in high applied magnetic field in type-II superconductors, making them more technologically relevant than type-I. Each vortex has a nonsuperconducting core with a radius on the scale of the coherence length ξ, and a circulating supercurrent that generates one quantum of(More)
La2-xSrxCuO4 nanowire devices have been fabricated and characterized using electrical transport measurements. Nanowires with widths down to 80 nm are patterned using high-resolution electron beam lithography. However, the narrowest nanowires show incomplete superconducting transitions with some residual resistance at T = 4 K. Here, we report on the(More)
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