Updated results on prototype chalcogenide fibers for 10-um wavefront spatial filtering

The detection of terrestrial planets by Darwin/TPF missions will require extremely high quality wavefronts. Single-mode fibers have proven to be powerful beam cleaning components in the near-infrared, but are currently not available in the mid-infrared where they would be critically needed for Darwin/TPF. In this paper, we present updated measurements on the prototype chalcogenide fibers we are developing for the purpose of mid-infrared spatial filtering. We demonstrate the guiding property of our 3rd generation component and we characterize its filtering performances on a 4 mm length: the far-field radiation pattern matches a Gaussian profile at the level of 3% rms and 13% pk-pk.Comment: 4 pages, 5 figures, to appear in the proceedings of the conference "Toward Other Earths, Darwin/TPF and the search for extrasolar terrestrial planets", held in Heidelberg, Germany, 22-25 April 2003, ESA SP-53

Receipt from George A. Haggerty

https://digitalcommons.salve.edu/goelet-new-york/1246/thumbnail.jp

Teaching a Person with Memory Impairment Smartphone Use for Emergencies during Outdoors Walking Case Report

Safety issues arise during the performance of activities as dementia advances. Occupational therapists collaborate with dementia clients and their caregivers to find solutions and strategies to prolong safe activity participation. Additionally, occupational therapists teach through demonstration showing engagement in specific activities may no longer be safe. We present the case of a 70-year-old male with mild dementia. His caregiver believes he needs to use a smartphone for safety during outdoors walking; the client’s enjoyed and valued occupation. This case report illustrates smartphone use may be difficult to learn for a person with mild dementia. It highlights the need for the caregiver and person with dementia to receive education together for best understanding. New technologies for community mobility such as outdoors walking are considered

High resolution spectroscopy of single NV defects coupled with nearby 13^{13}C nuclear spins in diamond

We report a systematic study of the hyperfine interaction between the electron spin of a single nitrogen-vacancy (NV) defect in diamond and nearby $^{13}$C nuclear spins, by using pulsed electron spin resonance spectroscopy. We isolate a set of discrete values of the hyperfine coupling strength ranging from 14 MHz to 400 kHz and corresponding to $^{13}$C nuclear spins placed at different lattice sites of the diamond matrix. For each lattice site, the hyperfine interaction is further investigated through nuclear spin polarization measurements and by studying the magnetic field dependence of the hyperfine splitting. This work provides informations that are relevant for the development of nuclear-spin based quantum register in diamond.Comment: 8 pages, 5 figure

Environment Assisted Metrology with Spin Qubit

We investigate the sensitivity of a recently proposed method for precision measurement [Phys. Rev. Lett. 106, 140502 (2011)], focusing on an implementation based on solid-state spin systems. The scheme amplifies a quantum sensor response to weak external fields by exploiting its coupling to spin impurities in the environment. We analyze the limits to the sensitivity due to decoherence and propose dynamical decoupling schemes to increase the spin coherence time. The sensitivity is also limited by the environment spin polarization; therefore we discuss strategies to polarize the environment spins and present a method to extend the scheme to the case of zero polarization. The coherence time and polarization determine a figure of merit for the environment's ability to enhance the sensitivity compared to echo-based sensing schemes. This figure of merit can be used to engineer optimized samples for high-sensitivity nanoscale magnetic sensing, such as diamond nanocrystals with controlled impurity density.Comment: 9 pages, 6 figure

Environment Assisted Precision Measurement

We describe a method to enhance the sensitivity of precision measurements that takes advantage of a quantum sensor's environment to amplify its response to weak external perturbations. An individual qubit is used to sense the dynamics of surrounding ancillary qubits, which are in turn affected by the external field to be measured. The resulting sensitivity enhancement is determined by the number of ancillas that are coupled strongly to the sensor qubit; it does not depend on the exact values of the coupling strengths and is resilient to many forms of decoherence. The method achieves nearly Heisenberg-limited precision measurement, using a novel class of entangled states. We discuss specific applications to improve clock sensitivity using trapped ions and magnetic sensing based on electronic spins in diamond.Comment: 4 pages, 3 figure

Implementation of HERS-ST in Iowa and Development / Refinement of a National Training Program

The Highway Economic Requirements System (HERS) is an economic model that uses highway performance monitoring system (HPMS) data to project future highway conditions and requirements. HERS is a highly complex model that, at the national level, uses samples of the highway network taken from the HPMS data. As a result, at the national level it is only used for aggregate network-level analysis (planning-level analysis). When the Federal Highway Administration’s Office of Asset Management was established in 1999, the office began developing the state version of HERS, or HERS-ST. HERS-ST has since evolved into a model that is specifically crafted for states. A DOS version of HERS-ST was demonstrated at a workshop attended by representatives of several state transportation agencies in 2001. Since then, several improvements have been made to the software, including updates for a Windows environment and the addition of GIS capabilities. The current project will yield a HERS-ST specifically for Iowa, but one that can be used as a model for other states